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M ED1CAL C HEMISTRY > 



INCLUDING THE OUTLINES OF 



Organic §1 Physiological Chemistry. 



BASED IN PART UPON RICHES MANUAL DE CHIMIE. 



C. Gilbert Wheeler, 

Professor of Chemistry in the University of Chicago, and in the 
Hahnemann Medical College. 

4 



S. J. WHEELER, 
Chicago. 

1879. 

I n ~ 



OTHER WORKS by PROF. WHEELER. 



DETERMINATIVE MINERALOGY. A practical guide to the recogni- 
tion of mineral species, chiefly by physical characteristics. 
Price $1.00. 

NATURAL HISTORY CHARTS. Five in number, one each of the fol- 
lowing: Mammalia; Birds; Reptiles and Fishes ; Invertebrates; 
Minerals, Rocks and Fossils. In all, over TOO illustrations. Wholly 
hand colored • Price of each chart, $7.00. The set, $30.00. 

NATURAL HISTORY PRIMER. A concise descriptive work on Zool- 
ogy aud Mineralogy. Price $1.00. 

CATALOGUS POLYGLOTTUS, Or classified list of the more important 
animals, minerals aud fossils in Latin, English, French, German and 
Spanish: for Scientific Travelers, Collectors, Curators of Museums 
and others. Price $2.00. 

IN PREPARATION. 

THE CHEMISTRY OF BUILDING MATERIALS. 



COPYRIGHT 

C. GILBERT WHEELER, 

1878. 



CONTENTS. 











PAGE 


Introductory, 


- 


- 


= 


7 


Classification of Organic Compounds, 




10 


Homologous Series, 




- 




12 


Hydrocarbons, 


- 


- 


- 


18 


Alcohols, 




~ 




44 


" Monatomic, 


- 


. 


- 


46 


" Diatomic, 




_ 




58 


" Triatomic, 


- 


= 


- 


64 


Ethers, 




- 




69 


Aldehyds, 


- 


- 


- 


85 


Acids, 




- 




90 


" MONATOMIC, 


. 


- 


- 


96 


w Polyatomic, - 




- 




112 


Alkaloids or Bases, 


- 


- 


- 


127 


" Artificial, 




- 


132 


i, 170 


" Natural, 


- 


- 


- 


137 


Neutral Fatty Bodies, 




- 




174 


Sugars, 


- 


- 


- 


181 


Glycosides, 




_ 




193 


Vegetable Chemistry, 


- . 


- 


- 


199 


Cellulose, - 




- 




205 


Starch, 


- 


- 


- 


210 


Dextrin, 




- 




214 


Gums, - • - 


- 


- 


- 


216 







PAGE. 


Animal Chemistry, 


- 


221 


Albuminoids, 


- 


225 


Fibrin, - - 


- 


231 


Casein, 


.. 


233 


Digestion, 


- 


236 


Saliva, 


- 


237 


Gastric Juice, 


- 


242 


Bile, 


- 


250 


Pancreatic Juice, 


- 


261 


Chyle, Lymph, 


_ 


270 


Blood, - 


- 


272 


H^EMOGLOBULIN, 


• - 


285 


Chemical Pathology of the Blood, 


294 


Respiration, 


- 


301 


Animal Heat — Muscular Power, 


316 


Assimilation, 


- 


321 


Secretion — 'The Urine, 


- 


333 


Chemistry of Normal Urine, 


- 


339 


" " Abnormal " 


- 


347 


Urinary Sediments, 


- 


352 


" Calculi, 


= 


353 


Analysis of Urine, 


» 


356 


" " Urinary Deposits, 


- 


364 


" Calculi, - 


- 


368 


Sweat, - - 


- 


370 


Milk, 


« 


376 


The Soft Tissues, 


- 


383 


Osseous Tissue, 


- 


396 


Dental " . 


- 


403 


Exudations, 


- 


407 



PREFACE. 



Medical chemistry has not as yet secured in Ameri- 
can colleges sufficiently pronounced attention to create 
a demand for text-books of considerable size or ex- 
tended scope. In these simple Outlines, therefore, no 
more has been attempted than this circumstance would 
appear to warrant. It is hoped that the necessary 
conciseness in method and form of expression has not 
resulted in any important sacrifice of perspicuity in 
thought or arrangement. 

It would have been easier to prepare a larger work. 
From the bewildering wealth of results afforded by the 
labors of investigators in this branch of science, the ap- 
propriate selection of that suited to the wants of stu- 
dents was by no means an easy task. 

It is assumed in these Outlines that those entering 
upon the study of Medical Chemistry have previously 
made themselves acquainted with Inorganic Chemistry 
as taught by some recent author, such as Miller or 
Barker, or have at least become familiar with the gen- 
eral principles of modern chemical philosophy. The 
author taking this for granted, has not, therefore, en- 
cumbered the work with a restatement of that which 
appertains to the theory of chemistry in general. 

In addition to the organic portion of Eiche's Man- 
uel de Chimie, a translation of which by the author 



PREFACE. 

has served in part as basis for these Outlines, the 
works of Miller, Fownes, Williamson, Roscoe, and 
others have been freely used, while the chemical 
journals of Europe and America, including their latest 
numbers, have been consulted and the data which 
they aiforded utilized. 

"Where the excerpta have been from journals of too 
recent issue to be found in standard authors, a reference 
in brackets has been made to the original source. Of 
the three series of numbers thus employed, the first 
has reference to the list of journals given at the close 
of this work, the second usually refers to the number 
of the volume, though sometimes to the year, the 
third indicates the page. 

Lest any regard the number of characteristic re- 
actions of the more important compounds as insuffi- 
cient, it should be stated, that it was not within 
the plan of the author to adapt this work to the 
requirements of an analytical manual. Not more 
than two or three analytical tests are therefore given 
as a rule, and even this number only in the case of the 
leading compounds. A similar explanation might be 
proffered to any who may miss the full technical de- 
tails relative to certain compounds which are usually 
given in works on applied, or technological chemistry. 

Throughout the work, the centigrade thermometer 
and the metric system of weights and measures are 
employed, unless otherwise specifically stated. 

C. Gilbert Wheeler. 
University of Chicago, December, 1878. 



ORGANIC CHEMISTRY. 



LNTKODUCTOKY. 

Organic chemistry is the science of the compounds 
of carbon. 

Only a small number of other elements are met 
with in natural organic substances; they are hydrogen, 
oxygen and nitrogen, sometimes also, sulphur, phos- 
phorus, and very rarely certain other elements. 

Chemists have succeeded in incorporating most of 
the elemental substances in organic bodies, yet the 
larger number even of the artificial compounds include 
only the four elements first named. 

Paraifine is found by analysis to contain only carbon 
and hydrogen, and is therefore called a hydrogen- 
carbide. The hydrocarbides are compounds so stable 
and fundamental that some chemists, as Schorlemmer 
for instance, have even defined organic chemistry as 
" the chemistry of hydrocarbons and their derivatives." 

From alcohol, or sugar, we may obtain carbon and 
water. These bodies therefore are composed of three 
elements : carbon, hydrogen and oxygen, and are called 
carbohydrates ; though by some chemists, this 
term is restricted to those compounds containing car- 



8 ORGANIC CHEMISTRY. 

bon with hydrogen, and oxygen in such proportions as 
would form water. 

If albumen is decomposed by heat, the result is not 
only carbon and water, but also ammonia ; this sub- 
stance accordingly is nitrogenous. 

The number of organic bodies is very great. As they 
are composed of a small number of elements only, it 
may be concluded that the latter unite in a very great 
variety of proportions ; it is therefore of much impor- 
tance to know the molecular grouping of these ele- 
ments. The mere fact that the kind and number of 
elements entering into a compound are known, is not 
sufficient proof that its molecular structure is really 
determined. Synthesis must often be employed to 
confirm the results of analysis. 

Berthelot has specially occupied himself with the 
synthesis of organic bodies, and has artificially produced 
a great number of them. Other chemists have 
experimented in the same direction during the last 15 
or 20 years. However, Gerhard t's opinion advanced 
in 1854; viz., " The vital force alone operates by syn- 
thesis and reconstructs the edifice demolished by 
chemical affinity," has ceased to be held as true. 

ISOMERISM. 

Carbon, hydrogen, oxygen and nitrogen are not only 
capable of uniting in a great variety of proportions, 
but these elements also furnish numerous isomeric 
bodies ; these comprise substances which, while com- 



ISOMERISM. y 

posed of the same elements, have different properties. 
Sometimes the physical properties alone are different ; 
we then have physical isomerism. 

When the chemical properties themselves are modi- 
fied, this is denominated chemical isomerism. Of the 
latter, two kinds are recognized. 

I. Polymerism / cyanogen and paracyanogen are 
examples of this variety of isomerism ; the latter is to 
be considered as cyanogen, GN condensed, thns 
(CN)n ; it is a polymeride of cyanogen. The weight of 
the molecule of these two substances is therefore dif- 
ferent. 

II. Metamerism. At other times the isomerism 
results from a different grouping of elements in the 
compound, the molecular weight remaining the same. 

We will illustrate this by two examples : 
a) Methyl acetate, 
aud b) Ethyl formiate. 

Acetic acid = H-0-C 3 H 3 0. 

Methyl hydrate, or methyl alcohol=H-0-CH 3 . 

When these two bodies react they furnish water and 
methyl acetate, CH 3 -0-C 2 H 3 0==C 3 H 6 2 . 

Formic acid=H-0-CHQ. 

Ethyl hydrate, or ethyl alcohol=H-0-C 2 H 5 . 

JNow formic acid contains CH 2 less than acetic acid, 
and hydrate of ethyl contains one molecule of OH 2 
more than does hydrate of methyl. As these substan- 
ces in reacting lose one molecule of water, it is there- 
fore clear that the compound obtained will have, like 
the preceding one, the formula C 3 H 6 3 . But these 



10 ORGANIC CHEMISTRY. 

two products are not identical substances, for the for- 
mer treated with alkalies regains the molecule of water 
which it had lost, reforming acetic acid and methyl hy- 
drate, while the latter regenerates formic acid and ethyl 
hydrate. 

These bodies accordingly differ in the arrangement 
of their molecule ; they are called metameric bodies. 

Finally there exist bodies which are isomeric, prop- 
erly so-called, possessing the same formula, having the 
same general reactions, the same chemical functions, 
and which differ only in a very few, chiefly physical, 
properties : such are oil of turpentine and oil of lemon, 
each having the formula C 10 H 16 . 

CLASSIFICATION OF ORGANIC COM- 
POUNDS. 

Chemical Types. — The idea of referring organic bod- 
ies to some simple model, or type, was originally work- 
ed out by Laurent and Gerhardt, 1846-53. though the 
germs of their ideas on classification are to be found in 
the earlier papers of the distinguished American 
chemist T. S terry Hunt. (Am. Jour. Sci. [2] xxxi.) 

The four principal types are : 

H' ) 

I. The hydrogen type, -p-, VorH 2 . 

II. The oxide or water type, tt' [ O' ' orH 2 0. 

H'j 

III. The nitride or ammonia type,H ' \ N ' ' ' or H 3 N. 



ORGANIC TYPES. 11 



H' 

TT / 

IV. The marsh gas type tt t 

H' 



VC 1Y orELC. 



Of the leading groups of organic bodies, we refer to 
the hydrogen type: hydrocarbides, aldehyds and the 
compounds of metals and metalloids with organic 
radicals. 

To the water type are referred the alcohols, ethers, 
mercaptans and anhydrides. 

To the ammonia type belong the amides, amines, 
and alkalamides, all of which are denominated com- 
pound ammonias. 

Marsh-gas is the type to which carbon dioxide is 
referred, as well as some of the more complex organo- 
metallic bodies. 

Further details as to the relation of each of these 
classes of compounds to their respective types will be 
given as each particular class is studied. 

Besides the simple type, Kekule has proposed com- 
pound types formed by the combination of two of the 
four types already given. Thus the types of ammonia 
and water combined serve as a pattern for carbamic 
and oxamic acids: 

JJ ' "\ Carbamic acid. Oxamic Acid. 

S "'"■ i}>, IK 
g: o- %\o < c '% o 



12 ORGANIC CHEMISTRY, 



HOMOLOGOUS SERIES. 



The members of a series of compounds which have 
the common difference of CIT 3 are said to be homolo- 
gous. Two or more such homologous series are termed 
isologous. 

The first idea of progressive series in organic 
chemistry was enunciated by James Schiel, of St. 
Louis, Mo., in 1842. It was afterwards adopted by 
Gerhardt unchanged, save only in name. (100-5-195.) 

The subjoined table will illustrate the nature of these 
series. Each vertical column forms a homologous 
series in which the terms differ by CH 2 , and each hori- 
zontal line an isologous series in which the successive 
terms differ by H 2 . The bodies of these last series are 
designated as the monocarbon, dicarbon group, etc. 



C H 4 C H 3 




C 2 H 6 C 2 H 4 C 2 H 3 




^3^8 C 3 H 6 C 3 H 4 


C 3 H 3 


C 4 H 10 C 4 H 8 C 4 H 6 


C 4 H 4 C 4 H 3 


C 5 H 12 C 5 H 10 C 5 H 8 


C 5 H 6 C 5 H 4 C 5 H< 


C 6 H 14 C 6 H 12 C 6 H 1C 


i C 6 H 8 C 6 H 6 C 6 H 



The terms of the same homologous series resemble 
one another in many respects, exhibiting similar trans- 
formations under the action of given re-agents, and a 
regular gradation of properties from the lowest to the 
highest ; thus, of the hydro-carbons, C n H 2n42j the low- 
est terms CH 4i C 2 H 6i and C 3 H 8i are gaseous at ordinary 
temperatures, the highest containing 20 or more car- 



HOMOLOGOUS SERIES. 



13 



bon-atoms, are solid, while the intermediate com- 
pounds are liquids, becoming more and more viscid and 
less volatile, as they contain a greater number of car- 
bon-atoms, and exhibiting a constant rise of about 20° 
C. (36° F-) in their boiling points for each addition of 
CH 2 to the molecule. 

The individual series are given in the following ta- 
ble, witb the names proposed for them by A. W. 
Hoffmann: 



Methane 


Methene 






CH 4 


CH 2 






Ethane 


Ethene 


Ethine 




C 2 H 6 


C 2 H 4 


C 2 H 2 




Propane 


Propene 


Propine 


Propone 


C 3 H 8 


C 3 H 6 


C 3 H 4 


C 3 H 2 


Quartane 


Q uar ten e 


Quartine 


Quartone Quartune 


C 4 H 10 


C 4 H 8 


C 4 H 6 


C4Q.4 4 XX 2 


Quintane 


Quintene 


Quintine 


Quintone Quintune 


5 H I2 


C 5 H 10 


C 5 H 8 


C 5 H 6 C5H4 


Sextane 


Sextene 


Sextine 


Sextone Sexto ne 


^6-t44 


C 6 H 12 


C 6 H 10 


C 6 H 8 C 6 H 6 



The formula in the preceding tables represent hydro- 
carbons all of which are capable of existing in the 
separate state, and many of which have been actually 
obtained. They are all derived from saturated mole- 
cules, C n H 2n+2i by abstraction of one or more pairs of 
hydrogen- atoms. 

But a saturated hydrocarbon, CH 4i for example, may 



14 ORGANIC CHEMISTRY. 

give up 1, 2, 3, or any number of hydrogen-atoms in 
exchange for other elements ; thus marsh gas, CH 4i 
subjected to the action of chlorine under various cir- 
cumstances, yields the substitution-products, 

CHaOl, CH 2 C1 2 , CHC1 3 , CC1 4 , 

which may be regarded as compounds of chlorine with 
the radicles, 

(CH 3 )', (CH 2 )", (CH)'", C»; 

and in like manner each hydrocarbon of the series, 
C n H 2n+2 , uiay yield a series of radicles of the forms, 

(QAm)', (CH*)", (C„H„)'" (C n H 2n _ 2 )*&c. 

each of which has an equivalent value, or combining 
power, corresponding with the number of hydrogen- 
atoms abstracted from the original hydrocarbon. Those 
of even equivalence contain even numbers of hydro- 
gen-atoms, and are identical in composition with those 
in the table above given ; but those of uneven equiva- 
lence contain odd numbers of hydrogen-atoms, and 
are incapable of existing in the separate state, except, 
perhaps, as double molecules. 

These hydrocarbon radicles of uneven equivalence 
are designated by Hoffmann, with names ending in yl, 
those of the univalent radicles being formed from 
methane, ethane, &c, by changing the termination 



HOMOLOGOUS SERIES. 



15 



ane into yl ; those of the trivalent radicles by chang- 
ing the final e in the names of the bivalent radicles, 
methene, &c. , into yl; and similarly for the rest. The 
names of the whole series will therefore be as follows : 



CH 4 


(OH 3 )' 


(CH 2 )" 


(OH)'" 


Methane 


Methyl 


Methene 


Methenyl 


C,H 6 


(W 


(C 2 H 4 )" 


(C 2 H 3 )'" 


Ethane 


Ethyl 


Ethene 


Ethenyl 


C 3 H 8 


(C 3 H 7 )' 


(C 3 H 6 )" 


(e 3 H 5 )'" 


Propane 


Propyl 


Propene 


Propenyl 


&c. 




&c. 


&c. 



From these hydrocarbon radicles, others of the 
same degree of equivalence may be derived by partial 
or. total replacement of the hydrogen by other elements, 
or compound radicles. Thus from propyl, C 3 H 7 , may 
be derived the following univalent radicles : — 

C 3 H 6 01 3 H S 01 4 8 H 5 

Chloropropvl Tetrachloropropyl Oxypropyl 

c 3 h 2 ci 3 6 c 3 H 6 ((m) - c 3 H 6 (]sro 2 ) 

Trichloroxy propyl Cyanopropyl. Mtropropyl 
C 3 H 4 (^TH 2 )0 C 3 H 6 (CH 3 ) . C 3 H 3 (C 2 H 5 ) 2 

Amidoxypropyl Methylpropyl Diethylpropyl. 

From the radicles above mentioned, all well-defined 
organic compounds may be supposed to be formed by 
combination and substitution, each radicle entering 
into combination, just like an elementary body of the 
same degree of equivalence. 



16 ORGANIC CHEMISTRY. 

TABLE TO ILLUSTRATE THE ARRANGEMENT OF THE MORE 



Series. 


Hydro- 
carbons. 


Sulphides. 


Chlorides or 
Haloid Ethers. 


Alcohols. 


General 
Formula. 


CriRzn 


CreH2«+i | q 
CnB.2Ji+i f & 


CrcH2W+iCl 


CriH.211+1 \q 




i. C H2 

2. C2 H4 

3. C 3 H 6 

4. C 4 H 8 

5. C5 Hio 
• 6. C 6 H12 

7. C7 H14 

8. Cg H16 

9. C 9 H18 
10. C10H20 


(C H 3 )2S 
(C2Hs)2S 

(C5Hn)2S 


C H3 CI 
C2H5 CI 
C3H7 CI 
C4H9 CI 

C5HIIC1 
C8HI7C1 


C H3 HO 
C2H5 HO 
C3H7 HO 
C4H9 HO 
C5H11HO 
C 6 Hi 3 HO 

CSH17HO 


Types 


§} 


g}0 


Hf 


l\° 



OEGANIC COMPOUNDS. 1? 

IMPORTANT ORGANIC COMPOUNDS IN HOMOLOGOUS SERIES. 



Mercaptans. 


Aldehyds. 


Acids. 


Simple Ethers. 


Compound Ethers. 


CnB.2n+i | c 
H f S 


CWH271-1 O ) 

h r 


C;zH2«-iO ) 


C?lH27l+I } n 

CwH2w+if u 


CwH2n+i J n 
Cn,B.2n-iOS 


C H3 HS 


C H 0,H 


HC H O2 


(C H 3 )20 


C H3 C H O2 1. 


C2H5 HS 


C2 H3 0,H 


HC2 H3 O2 


(C2Hs)20 


C2HS C2 H3 O2 2. 




C3 H5 0,H 


HC3 H5 O2 




C2HS C3 H S O2 3. 


C4H9HS 


C4 H7 0,H 


HC4 H7 O2 




C2HS C4 H7 O2 4. 


CsHnHS 


C5 H9 O.H 


HC5 H9 Os 


(C 5 Hii) 2 


CSH11C5 H9 O2 5. 




C6 HnO,H 


HC 6 H11O2 




C2HS C 6 H11O2 6. 




C7 Hi30,H 


HC7 H13O2 
HC 8 H15O2 
HC9 H17O2 




C8H5 C7 H13O2 7. 
C2H5 Cg H1SO2 8. 
C2H5 C9 H17O2 9. 




CioHi9H,0 


HC10H19O2 


(CioH2i)30 


C2H5 C10H19O2 10. 


g[o 


H i 


i}o 


Hf° 


Ih 



18 OBGANIC CHEMISTRY. 

CAKBIDES OF HYDEOGEK 

Tlie origin or preparation of these compounds, also 
called hydrocarbides, and their properties, physical 
and chemical, all differ largely. 

They are unlike the hydrogen combinations studied 
in inorganic chemistry inasmuch as they possess but 
feeble chemical energy Among the carbides are: 
acetylene, marsh-gas or methane, ethylene, oil of tur_ 
pentine and of lemon, benzol, naphthalin, petroleum, 
caoutchouc, gutta-percha, etc. 

The hydrocarbides will be divided into six series, 
they are all built upon the type of a molecule of hy- 
drogen, or H' ) 

w\- 

FIBST SEEIES. 

General Formula, CnH2 n — g. 

ACETYLENE, OR DIHYDROGEN DICARBIDE. 

Discovered by Davy and composition determined by Berthelot. 

Formula, C2H2. 

Specific Gravity, 0.92. Density, 13. Molecular weight, 26. 

Direct combination of Carbon and Hydrogen. 

Up to comparatively recent times it has been con- 
sidered impossible to unite earbon and hydrogen di- 
rectly. Berthelot, however, succeeded in doing this in 
the year 1863. 

Preparation. — The apparatus which he employed 



CAEBIDES OF HYDKOGEJS. 19 

in this remarkable synthesis, consisted of a glass flask, 
provided with two lateral tubulures through which 
passed two metallic rods, terminating in carbon points, 
and which approached so as to form, when connected 
with a powerful battery, an electric arc. The corks 
through which these rods passed were provided with 
another opening each, to which a tube was adapted. 
Through one of these tubes hydrogen was admitted 
and through the other the products of the reaction 
passed as they were formed. 

The gas was collected in a solution of cuprous 
chloride in ammonia. A red-precipitate, acetylide of 
copper was formed, which was thrown upon a filter and 
treated with hydrochloric acid in a flask, whereupon 
acetylene was set free. 

Many organic compounds produce acetylene on 
subjecting their vapors to the action of electric dis- 
charges. 

Acetylene is also produced, as a rule, whenever or- 
ganic matter is decomposed by heat. 

Peopeeties. — Acetylene is a colorless gas, having a 
disagreeable odor. It is moderately soluble in water, 
and is difficultly liquified. It is decomposed, at about 
the temperature at which glass melts, into carbon, 
hydrogen, ethylene, ethyl hydride and condensed 
hydrocarbides, among which Berthelot has found ben- 
zol. Thenard has recently obtained it both as a liquid 
and a vitreous solid. (9 — 78 — 219.) 

Acetylene burns with a fuliginous flame. It de- 
tonates violently and without residue when mixed with 



20 ORGANIC CHEMISTRY. 

2.5 volumes of oxygen. Cuprous acetylide is an ex- 
plosive body. It is sometimes formed in brass gas- 
pipes, and has been the cause of fatal accidents. 

Chlorine acts upon acetylene with extreme energy; 
there is often detonation accompanied by light. On 
moderating the action the compound C 2 H 2 C1 2 can 
be obtained, which, as well as the body C 2 H 2 C1 4 , 
can also be prepared by the action of antimonic chlo- 
ride upon acetylene. 

As acetylene is not uncommonly studied in con- 
nection with inorganic compounds, a more detailed ac- 
count of this hydrocarbide need not be given here. 

Acetylene is the prototype of a homologous series 
of hydrocarbides, of which the general formula is, 

C n H 2n _ 2# 

The following members of this series are known: 

Allylene, - - - - C 3 H 4 

Crotonylene, - - - C 4 H 6 

Valerylene, - - - C 5 H 8 

Rutylene, - C 10 H t8 

Benzylene, - C 15 H 38 . 



ETHYLENE. 21 



SECOND SEEIES. 

General formula, C n H2n. 
ETHYLENE. 

Synonyms: Elayl, Olefiant gas. 

Formula C 3 H 4 . 

Sp. Gr. 0.97. Molecular weight, 28. 

This gas, for no good reason other than custom, is 
always studied in inorganic chemistry, usually in con- 
nection" with the consideration of illuminating gas, of 
which, with methane, it forms a prominent constit- 
uent. 

Ethylene is the type of a class of homologous hydro- 
carbides, of which the general formula is : 

Each member of the series is related to an alcohol 
from which it may be obtained on treatment with 
bodies having a great affinity for water, as sulphuric 
acid or zinc chloride. 

C n H 2n+2 + 2 — H 2 = C n H 3n . 



22 ORGANIC CHEMISTRY. 

We note the following members of this series 



Ethylene, - 


- 


- C 2 H 4 


Propylene, 


_ 


C 3 H 6 


JButylene, - 


- 


- C 4 H 8 


Amylene, 


- 


C 5 H 10 


Hexylene, 


- 


- C 6 H 12 


Heptylene, 


- 


C, H 14 


Octylene, - 


- 


- C 8 H 16 


Nonylene, 


- 


C 9 Hl8 


Paramylene, 


- 


- C 10 H 30 


Cetene, - 


- 


CiiH 33 


Duodecylene, 


- 


12 H 24 


Tridecylene, (Paraffin?)* 


^13^26 


Tetradecylene, 


- 


C 14 H 28 . 



*A. (x. Pouchet(66— [3] 4 — 868) lias prepared from paraffin, by 
oxydation with nitric acid, paraffin acid, C24H43O2, from which 
he deduces C24H50 as the formula for paraffin. 



METHANE. 23 



THIKD SEEIES. 

General formula, C n H-an+a* 
METHANE. 

Discovered by Volta in 1778. 

Synonyms; Methyl hydride, Marsh gas, Formene. 

Formula CH 4 or CH 3 , H. 

Sp. Gr. 0.559. Molecular weight, 16. 

Permanent gas, not liquifiable, neutral. 

Not discussed in detail here for the same reasons as 
given under Ethylene. 

Methane is the first member of the following very 
important homologous series : 

C H 4 methyl hydride, or methane. 



C 2 H 6 


ethyl 


a 


" ethane. 


C 3 H 8 


propyl 


a 


" propane. 


C 4 H 10 


butyl 


a 


" butane. 


C 5 H 12 


amyl 


a 


" amane. 


C 6 H 14 


hexyl 


a 


" hexane. 


C 7 H 16 


heptyl 


a 


" heptane. 


C 8 H 18 


octyl 


« 


" octane. 


G9H20 


nonyl 


a 


" nonane. 


^ioH-22 


decyl 


u 


" decane. 


C11H24 


undecyl 


a 


" undecane. 


C^H^ 


bidecyl 


u 


" bidecane. 



24 



OEGANIC CHEMISTRY. 



a 



tridecane. 
" tetradecane. 
" pentadecane. 
" hexadecane. 



C 13 H28 trideeyl " 

C^Hgo tetradecyl " 

C 15 H32 pentadecyl " 

C 16 R M hexadecyl " 

Nearly all the members of this series have been 

found in American petroleum, mixed with members 

of the preceding, or ethylene, series. 

Crude petroleum, refined by fractional distillation, 
is still a mixture of various hydrocarbons. 

The commercial names given to the products sep- 
arated at the different boiling points, do not appertain 
to chemical compounds, or bodies having a definite 
composition. 

Subjoined is a table based on Dr. C. F. Chandler's 
Eeport on Petroleum, (100 — '72-41) showing the 

PKODUCTS OF THE DISTILLATION OF CRUDE PETROLEUM.* 



NAME. 


O a 

a 3 


si 

Pm 2! 


pq 


CHIEF USES. 


Cymogene . . 


IK 

, 

4 
55 

19% 


.625 

.665 

.706 
.724 
.742 

.804 

.847 

.833 

Solid. 


0°C. 

18.3 

48.8 
82.2 
104. 4 
148.8 

176.6 

218.3 
301.6 


j Generally nncondensed — used in 
j ice machines. 

j Condensed by ice and salt— used as 
\ an anaesthetic. 

Used in making "air-gas. " 
( Used for oil-cloths, cleaning, adul- 
•< terating kerosene, etc. For paints 
( and varnishes, 

Used to adulterate kerosene oil. 




C Naphtha 

B Naphtha.., 

A Naphtha 


Kerosene oil 

Mineral sperm 

Lubricating oil 

Paraffin 


Ordinary oil for lamps. 
Lubricating machinery. 













*Re-arrangedfrom Dr. C. F. Chandler's Report on Petroleum, presented to 
the Board of Health, of the City of New York, 1870. 



METHANE. 25 

UNSAFE KEROSENE. 

Many accidents occur by explosion of lamps, when 
kerosene oil contains too much of the lighter oils, ben- 
zine and naphtha. This makes the oil too readily in- 
flammable, for the lighter oils are driven out by heat- 
ing (as when a lamp or kerosene stove is burning), and 
their vapors mixed with the oxygen of the air form a 
dangerous explosive mixture. There is a law requir- 
ing manufacturers to keep kerosene oil free from these 
lighter oils, unfortunately not always faithfully en- 
forced. 

The temperature at which kerosene, on heating in 
an open vessel, emits vapors which readily catch fire 
on approaching a burning body, is called, technically, 
the "flash point/' and that at which the kerosene itself 
inflames is called the "burning point." 

FOSSIL RESINS, AND BITUMEN. 

These substances include amber, retinasphalt, as- 
phalt, retinite, and many other allied bodies which are 
chiefly contained in the tertiary strata. In many in- 
stances they are the products of the action of an ele- 
vated temperature upon vegetable bodies; and when 
this is the case, they form irregular deposits which im- 
pregnate the strata around. In many cases the bitu- 
mens occur in regular beds, which appear to have been 
formed in a manner similar to the deposits of true coal. 

Certain important building stones have been found 
to be more or less impregnated with bitumen. 

Such is the limestone obtained at the artesian well 



26 ORGANIC CHEMISTRY. 

quarry in the city of Chicago, and the celebrated 
Buena Yista, (Ohio,) sandstone used extensively in 
Cincinnati; also employed at Chicago in various 
prominent public buildings, as the post-office and 
Chamber of Commerce. The author, in making a 
chemical examination of the latter stone for the 
United States Treasury Department, found it to con- 
tain 2.3 per cent, bituminous matter. 



BENZOL. 27 



FOUETH SEKIES. 

General formula C n H2n-6. 

BENZOL. 

Synonyms ; Benzene, Benzine. 

Formula C6H 6 . 

Sp. Gr. 0.88. Molecular weight, 78. 

Sp. Gr. of vapor 2.70. 

Density" " 39. 

Solid at 4°. Boils at 80.5°. 

Benzol is obtained, with acetylene and ethylene, in 
the decomposition of organic substances by heat, 
and its production is especially favored when the 
temperature is kept at a high point for some time. 

Ethylene and methane form at a tolerably low 
temperature. Acetylene, which is richer in carbon, 
is produced at a higher temperature. Benzol and 
especially napthalin, being still more carbonaceous, 
are formed at an extremely high temperature. 

Berthelot has prepared benzol synthetically by con- 
ducting methane tribromide, CHBr 3 , over red-hot 
copper : 

6(CHBr 3 )+9Cu=C 6 H 6 +9CuBr 2 . 

Benzol may be considered as condensed acetylene: 
C 6 H 6 =(C 2 Ha) 3 . 



28 ORGANIC CHEMISTRY. 

Originally, benzol was prepared by a process analo- 
gous to that which furnishes methane, i. e., by distill- 
ing benzoic acid with lime, 

C 7 H 6 3 +CaO = Ca C O s +C 6 H 6 . 

At present it is obtained in immense quantities from 
the tar which is formed as an accessory product in the 
manufacture of illuminating gas. 

At the high temperature of the gas-retort other pro- 
ducts, homologous with benzol, are formed as well; 
viz.: 



Toluene 


C 7 H 8 


boils at 110° 


Xylene 


^8 H t0 


u ic 139 o 


Cumene 


C 9 H 12 


" " 165° 


Cymene 


C10H14 


" " 180° 



and other hydrocarbides, as napthalin C 10 H 8 , anthra- 
cene, also various sulphur compounds, notably carbon 
bisulphide; several oxygenated compounds, as phenol 
C 6 H 6 0, cresylol C^H 8 ; nitrogenous compounds, 
as aniline C 6 H 7 N, and various members of its 
homologous series. 

Benzol is a colorless, neutral liquid, with a specific 
gravity of 0.89, almost insoluble in water but soluble 
in alcohol and ether. 

It dissolves sulphur, phosphorus, iodine, the differ- 
ent resins, and fatty substances ; this latter property 
causes it to be employed similarly with commercial 
" benzine' ' for cleansing purposes. Care must be taken 
to rub with a piece of cloth having an open texture, 



BENZOL. 29 

that it may remove the benzol by absorption, without 
which the spot would reappear after evaporation of the 
solvent. 

Benzol burns with a fuliginous flame. Nascent 
oxygen gives with it various products, and notably 
oxalic acid and carbon dioxide. 

Chlorine and bromine yield crystalline compounds 
with benzol. Benzol is the simplest member of a 
group of bodies known as the aromatic compounds, of 
which we shall proceed to describe some of the more 
important. 

For distinguishing benzol from the benzine of com- 
merce, which is made from petroleum, Brandberg 
recommends to place a small piece of pitch in a test 
tube, and pour over it some of the substance to be ex- 
amined. Benzol will immediately dissolve the pitch 
to a tar-like mass, while benzine will scarcely be col- 
ored. 

Nitro-benzol C 6 H 5 ]Sr0 2 . 

This body is obtained by treating benzol with fuming 
nitric acid. 

6 H 6 +HN0 3 = C 6 H 5 (N0 2 )+H 2 0. 

Nitro-benzol is a yellowish oil, crystallizing at 37°, 
has a sweet taste and an odor which has led to its use 
in perfumery under the name of essence of mirbane. 
Taken internally it acts as a poison. 

On treatment of nitro-benzol with nascent hydrogen, 
hydrogen sulphide, or other reducing agent, we obtain 



30 ORGANIC CHEMISTRY. 

aniline, which is a colorless liquid, boiling at 182°. 
It does not act upon litmus, yet combines with the 
acids, forming crystallizable compounds. 

Aniline gives with chlorine, bromine and nitric acid 
products of substitution which are very numerous and 
well denned. It reacts upon the iodides of methyl, 
ethyl, etc., forming the corresponding amines, or bodies 
constructed on the type of ammonia, having one or 
more of the hydrogen atoms replaced by an organic 
compound radicle: 



C„H 5 



Aniline C 6 H 7 JSr = N" { H 

Methylaniline C 7 H 9 lSr = N \ CH* 

! Cells 
CH 3 . 
C 2 H 5 

C 6 H 5 or, when free, (C 6 H 5 ) 2 , is the radicle phenyl, 
hence aniline is properly phenylamine. 

Aniline has, during the last score of years, acquired 
great importance, as, under the influence of oxydizing 
bodies, it forms most remarkable tinctorial com- 
pounds. 

If a small quantity of aniline is added to a solution 
of chloride of lime, the liquid is colored violet, which 
color disappears in a few moments. In 1858, Perkins 
obtained, by the action of potassium bichromate and 
sulphuric acid, a beautiful purple, which is known in 



BENZOL. 31 

commerce as mauve. Shortly after, Yerguin obtained 
a magnificent red coloring matter on heating aniline 
with tin dichloride. 

This substance, known under the names of aniline- 
red, fuchsin, magenta, etc., is now very economi- 
cally obtained with arsenic oxide in place of the tin 
dichloride, which is reduced to arsenous oxide by the 
reaction. 

Hoffmann has shown that aniline-red is a* salt of a 
colorless base, which he calls rosaniline; this substance 
has the formula C20H21N3O, or CaoH 19 N3,H 2 0. 

In the past few years there have been produced 
green, yellow and black colors, all originating from 
aniline. These substances dissolve in alcohol, and dye 
wool and silk without in any way weakening the fabric. 
They have a magnificent lustre, but their permanency 
is rot of the highest grade. 

The consumption of aniline for dyeing has now come 
to something enormous, amounting in Germany alone 
to over 15,000 tons per annum. 

The aniline colors are employed in injecting tissues 
for microscopic preparations. 

For a fuller account of the aniline colors, a larger 
work should be consulted. 

The history of aniline affords one of the most re- 
markable instances of the value of scientific chemical 
research, when perseveringly and skillfully applied, 
for at first few substances seemed to promise less; 
and the gigantic manufacturing industry at present 
connected with this compound, in its applications as a 



32 ORGANIC CHEMISTRY. 

tinctorial agent, offers a singular contrast to the earlj 
experiments upon this body, when a few ounces fur- 
nished a supply which exceeded the most sanguine ex- 
pectations of the early discoverers of this body. 

Phenol, C 6 H 6 0. 
Synonyms: Hydrate-of phenyl, carbolic acid or phenic acid. 

It occurs in castoreum, though usually procured from 
the portions of coal-tar distilling over between 170° 
and 195°. They are agitated with caustic soda, 
water added to separate the insoluble oils, and the 
phenol dissolved in the alkali is liberated as a crys- 
talline mass, on decomposing the potassium compound 
with hydrochloric acid. 

Salicylic acid, distilled with an excess of lime, also 
furnishes phenol; 

C 7 H 6 3 + CaO = CaC0 3 + C^O. 

Ifphenyl-sulphuricacid, V 5 > S0 4 , obtained by di- 
rect action of sulphuric acid uj>on phenol, is heated 
with potassium hydrate to about 300 ° , potassic phenol 
CglLsKO is obtained. Phenol is therefore obtained 
from benzol under the same conditions as alcohol is 
obtained from ethylene, the corresponding hydro- 
carbide. 

Phenol crystallizes in handsome needles, fusible at 
34° and boiling at 188°. It is little soluble in water, 



PHENOL. 33 

very soluble in alcohol and ether. Phenol furnishes 
with chlorine, bromine and iodine numerous substitu- 
tion products. 

Phenol has come, like alcohol, to have a generic 
signification, there being a number of analogous com- 
pounds, though only this, the ordinary phenol, is an 
important body. Heated with concentrated nitric 
acid, it furnishes yellow, very bitter, crystals of the 
body known as 

Picric or Carb azotic acid. 

Picric acid is also formed when silk, benzoin, aloes, 
indigo, etc., are treated with nitric acid. 

This acid is very largely used in dyeing, either di- 
rectly to produce a yellow color, or, combined with in- 
digo, to produce a green. 

Phenol, though called carbolic acid, does not decom- 
pose the carbonates, or combine with the metals to 
form true salts. Phenol dissolves in sulphuric acid 
without coloration, if pure, and forms phenyl-sulphuric 
acid or sulpho-carbolic acid 

° 6 l 5 }so 4! 

which gives definite salts with the metals. One of 
these, the phenyl- sulphate or sulpho-carbolate of so- 
dium NaC 6 H 6 S0 4 , is claimed to have valuable proper- 
ties as a prophylactic against scarlet fever. 

Phenol gives certain reactions of the alcohols ; this 



34 ORGANIC CHEMISTRY. 

somewhat explains the origin of the name given it by 
Berthelot. This "body is the type of a class of com- 
pounds which contains: 

Cresylol obtained from creosote C? H 8 O 

Phlorylol s < " " . C 8 H 10 O 

Thymol " " essence of thyme Ci H 14 O. 

PHYSIOLOGICAL ACTION OF PHENOL. 

Phenol attacks the skin, producing a white stain. 
It coagulates albumen and is employed with great 
success as an antiseptic and disinfectant. It is used 
externally in a diluted state to dress wounds which 
suppurate, also in many surgical cases. 

It is sometimes used internally. Large doses of it 
are poisonous. Carbonate and especially saccharate of 
calcium are considered as antidotes for phenol. Grace 
Calvert has announced that olive or almond oil is a 
still better antidote. 



OIL OF TUKPENTINE. 85 



FIFTH SEKIES. 

General Formula, C n H2n— 4. 
ESSENCE, OK OIL OF TURPENTINE. 

Formula C10H16. 

Density of vapor compared with air 4.7. 

Molecular weight, 136. 

Boils at 160° 

Turpentine is extracted from several varieties of the 
family of Conifer^ notably from the pine, fir and 
larch. 

The products vary somewhat with the nature of the 
tree, but they have many common characteristics; 
their composition is the same, their density is nearly 
identical and their boiling point very nearly so. Their 
rotary action on the solar ray varies largely. 

Isomeric carbides are found in other families of 
plants, in the aurantiacece family for instance, as the 
lemons and oranges. These contain carbides very dif- 
ferent, as evidenced by their odors and other physical 
properties, also different in certain chemical relations, 
yet having the same composition as oil of turpentine. 
There are also various polymers of this carbide. 

This entire series of hydrocarbons can be divided 
into three groups. The first contains carbides having 



36 ORGANIC CHEMISTRY. 

the formula C 10 H 16 , their boiling points being below 
200°, and including : 





Density. 


Boiling at 


Oil' of turpentine, 


.0.86 


157° to -160°. 


" cloves, 


0.92 


140° " 145°. 


" lemon, 


0.85 


170° " 175°. 


u orange, 


0.83 


175° " 180°. 


" juniper, 


0.84 


about 160°. 


" bergamot, 


0.85 


" 183°. 


" P e PP er > 


0.86 


" 167°. 


" elemi, 


0.85 


" 180°. 



The carbides of the second group have the formula 
C^H^ their boiling point is above 200°, they are: 

Oil of copaiva, 0.91 245°. 

" cubebs, 0.93 240°. 

The third group contains the non- volatile carbides, 

such as 

Density 

Caoutchouc, - 0.92. 

Gutta-percha, - - - 0.98. 

The rotary power, constant for each, varies with the 
different species. 

French oil of turpentine causes the plane of polar- 
ization to deviate to the left; the American variety 
turns it 13° to the right; oil of lemon causes a devia- 
tion of 50° to the right; in the case of essence of 
elemi the deviation amounts to 100°. Some of the 



OIL OF TURPENTINE. 37 

essential oils of the first group contain oxygen com- 
pounds as well as the carbohjdrides. 

The principal chemical differences between the 
members of the group are the facility with which they 
are oxydized and their reaction with hydrochloric 
acid. Essence of turpentine becomes resinous rapidly 
when exposed to the air and finally solidifies. Es- 
sence of lemon becomes viscid after a considerable 
time. Hydrochloric acid produces, with essence of 
turpentine, a liquid and a solid compound, having each 
the same composition, O 10 H 16 , HC1, which, after a 
few weeks, becomes a dichlorhydride, (by some denomi- 
nated a dichlorhydrate), C 10 H 16 ,2HC1. Essence of 
lemon also gives two dichlorhydrides at once, one 
liquid, the other solid. 

Oil of turpentine may be obtained in a pure state, 
on distilling the commercial article in a vacuum. 
Thus obtained, turpentine is colorlesSj limpid, very 
volatile, and has a characteristic odor. It is insoluble 
in water; very soluble in alcohol and ether. It burns 
with a smoky flame; on exposure to the air it oxydizes 
and becomes resinous. The same effect is produced 
more rapidly with oxide of lead and some other ox- 
ides which render the oil siccative and suitable for use 
in painting. J. M. Merrick (100-4-289) has noticed 
the circumstance, important in its technical applica- 
tions, that oil of turpentine attacks metallic lead quite 
strongly; tin, on the other hand, not at all. Turpen- 
tine, if exposed to the air, mixed with a solution of 
indigo, absorbs oxygen and transfers it to the indigo, 



38 ORGANIC CHEMISTRY. 

which loses its color, yielding a product of oxydation 
called isatin. Under these circumstances, the turpen- 
tine does not change, and a given quantity of the es- 
sence can absorb several hundred times its volume of 
oxygen, and oxydize an indefinite quantity of indigo. 
This oxygen is probably the active modification, or 
ozone. Heated to 300° in a hermetically sealed tube, 
it changes into two products, one, isomeric, called iso- 
turjpentine, which boils at 177°, and which exerts a 
rotatory power of 10° to 15° to the left; the other, a 
polymer called onetartereberithene^ C20H32 boiling at 
360°. 

OTHER SERIES OF HYDROCARBIDES. 

Cinnamene C 8 H 8 is a very refractive liquid with 
a density of 0.924, boiling at 146°. Styrol which 
is produced from storax is converted at 205°, into a 
polymeric solid, termed Meta-styrol or Draconyl. If 
styrol is made to act upon acetylene, or ethylene, at 
a red heat, there is obtained the very important hydro- 
carbide naphthalin Ci H 8 . This is a body crystalliz- 
able in very handsome plates, and is ordinarily 
obtained from coal tar by distillation between 200° 
and 300°; heavy oils pass over, out of which naphtha- 
lin crystallizes; on cooling, the mass is pressed and 
purified by sublimation. It fuses at 79° and distils at 
220°. 

Naphthalin is associated in coal tar with a hydro- 
carbide, beautifully crystallizing in long needles, fus- 
ing at 93° and boiling at 285°. This is acenaphtene 



ALIZARIN. 39 

C 12 H 10 . Another hydrocarbide is also found in this tar, 
anthracene. Its formula is O 14 H 10 . It forms very 
diminutive crystalline plates fusing at 210° and boil- 
ing at 360°. Its vapOr is extremely acrid. 

This body has recently enabled chemists to repro- 
duce the coloring principle of madder; alizarin 
C I4 H 8 4 . It is obtained on oxydizing anthracene by 
means of a mixture of bichromate of potassium and 
sulphuric acid, which." gives oxy anthracene C 14 H 8 2 . 
This, with fused potassa, furnishes a combination of 
potassium and alizarin, from which the latter is pre- 
cipitated by an acid. It has the form of brilliant 
bronze-colored needles, identical with natural alizarin 
obtained from madder. 

Alizarin sublimes at 215° and is very stable, little 
soluble in cold water, but readily soluble in boiling 
water. It is easily dissolved in alcohol, ether, and car- 
bon bisulphide. 

Its chemical character, not quite well defined as 
yet, appears to place it among the phenols. (See 
page 33.) 

The artificial production of alizarin from anthra- 
cene, thus furnishing a cheap substitute for madder, 
the chief dye-stuff used in printing calicoes, is one of 
the latest and most noteworthy triumphs of organic 
chemistry. Thousands of acres of land in Europe, 
especially in Alsatia, now devoted to the culture of 
madder, may be restored to cereal or other food agri- 
culture. 



Before leaving the hydrocarbons proper, it should 



40 ORGANIC CHEMISTRY. 

be stated that compounds of carbon and hydrogen of 
extra-terrestrial origin have been found in certain met- 
eorites, by J. Lawrence Smith. (80-76-388.) 

CAMPHOR. 

Camphor is usually considered at this point, on ac- 
count of its intimate relation to the oxydized essential 
oils in composition, and to turpentine in many chemical 
reactions. 

Berthelot regards camphor as an aldehyd. Kekule 
places it among the ketones. 

Camphor exists in various parts of the Laurus 
camphora. To obtain it, the wood is finely divided 
and heated with water in a metallic vessel, closed by a 
cover filled with straw. The camphor is condensed in 
grayish crystals on the straw, forming the crude cam- 
phor of commerce ; it is afterwards sublimed in a glass 
retort as a further purification. 

Camphor is a crystallized body, having a burning 
taste and an aromatic odor. Its density is 0.99 at 
10°. It is elastic and with difficulty pulverized, which 
can, however, be easily effected on moistening with a 
few drops of alcohol. Water dissolves only about -^-^ 
part of it ; thrown upon pure water it floats on the 
surface with a gyratory motion. It is soluble in alco- 
hol, ether, acetic acid and essential oils ; it is sublimed 
at ordinary temperatures where kept in close vessels, 
and deposits again on the cooler side of the recep- 
tacle. 

It burns with a smoky flame and oxydizes on being 



RESINS, BALSAMS, GUM-RESINS. 41 

boiled with nitric acid, yielding camphoric acid 
O 10 H 16 O 4 which is bibasic. Heated with zinc chloride or 
anhydrous phosphoric acid, it furnishes Cymol C 10 H 14 . 

The author found (1-146-73; that on treatment of 
camphor with hypochlorous acid he obtained the new 
body, C 10 H 15 ClO, which he denominates monochlor- 
camphor\ this, on treatment with alcoholic potassium 
hydrate, yielded oxy camphor C 10 H 16 O 2 . 

Camphor is very extensively employed in medicine 
and pharmacy. 

RESINS, BALSAMS, GUM-RESINS. 

These bodies are products of the oxidation of essen- 
tial or volatile oils. The name of gum-resin is applied 
to those which contain a gum, and balsam to those 
which contain essential oils and an acid, usually cin- 
namic or benzoic, in addition to the resin which is 
presented in both. A. B. Prescott, the eminent au- 
thority on proximate analysis, defines balsams as " natu- 
ral mixtures of volatile oils with their oxidation pro- 
ducts, — resins and solid volatile acids. " 

They are substances more or less colored, hard and 
brittle. They are fusible, n on- volatile, and burn with 
a fuliginous flame. They are insoluble in water, gen- 
erally soluble in alcohol, ether and essential oils. 

Several of them are acid. This is the case with the 
most important of them, as the resin of the pine, called 
colophony, from which three isomeric acids have been 
obtained — the pinic, sylvic, and pimaric, C20H30O2. 



42 ORGANIC CHEMISTRY. 

This resin constitutes the fixed residue obtained on 
distilling crude turpentine* It is used for preparing 
varnish, in soldering, and in certain combinations with 
the alkalies, called resin-soaps. 

Subjoined are given the names and the origin of the 
principal resins, oleo-resins, gum-resins and balsams. 
"With some, the position assigned them in this classi- 
fication is not definitely settled. 

EESINS. 

Amber is found in the lignites and in the alluvial 
sands of the Baltic. 

Arnicin, the active principle of Arnica Root. 

Cannabin, the active principle of Indian Hemp* 

Castorin, a secretion of the Beaver {Castor). 

Ergotin(?), the active principle of Ergot of common 
rye. 

Mastic, a resinous exudation of the Mastic, or Lent- 
isk tree. 

Burgundy Pitch, an exudation of the Spruce Fir, 
Abies excelsa. 

Pyrethrin, the active principle of the Pellitory root. 

Pottlerin, a crystalline resin from Kamala, the min- 
ute glands which cover the capsules of Bottler a tinc- 
toria. 

OLEO -EESINS. 

Copaiva, a resinous juice of the eopaifera officinalis 
found in Spanish America. 

Wood-oil, an oleo-resin from the Dipt ero carpus 
turbinates. 



RESINS, BALSAMS, GUM-RESLTSTS. 43 

Elemi, an exudation of an unknown tree, (probably 
C armarium commune). 

Common Frankincense, a concrete turpentine of the 
Pinus tceda. 

Canada balsam, the turpentine of the Balm of Grilead 
Fir, (Abies balsamea). 

Storax, from the Liquidambar orientale. 

GUM-RESINS. 

Ammoniacum, an exudation of the Dorema ammo- 
niacum. 

Assafoetida, a gum resin obtained by incision from 
the living root of the JVarthex assafoztida. 

Gamboge, obtained from the Garcinia morella. 

G-albanum, from the galbanum officinale. 

Myrrh,an exudation of the Balsamodendronmyrrha. 

BALSAMS. 

Benzoin, obtained from incisions of the bark of 
Styrax benzoin. 

Balsam of Peru, from the Myroxylon Pereirm. 

Balsam of Tolu, obtained from incisions of the bark 
of Myroxylon tuluifera. 



Caoutchouc is the hardened juice of Ficus elastica^ 
Jatropha elastica, Siphonia eahuchu, and other plants. 

Grutta-percha is the concrete juice of the peroha 
(Malay) tree the Isonandra percha, a sapotaceous plant. 



44 ORGANIC CHEMISTRY, 



ALCOHOLS. 

GENERAL DEFINITION AND CHARACTERISTICS. 

This name is given to a class of neutral bodies as 
important as they are numerous. Their essential 
characteristic is that of reacting upon acids so as to 
form water and a class of bodies called ethers. 

The number of alcohols is very considerable. There 
are several distinct varieties of alcohol recognized. 

I. Those built on the type of one molecule of 
water: 

Vr 5 [ O, ethyl or common alcohol. 

II. On two molecules of water : 

2 tt 4 [ 2 , ethylene alcohol or glycol. 

III. On three molecules of water : 

V 5 j- 3 , glycerine and thus on. 

They may be defined as bodies built on the type of 
one or more molecules of water having one-half of the 
hydrogen replaced by a hydrocarbide radicle. 

MONATOMIC ALCOHOLS, 

or those formed on the type of one molecule of water, 



ALCOHOLS. 45 

of which ordinary alcohol is the best studied, are 
characterized by the fact that they contain one atom 
of oxygen only, and that by reaction with the mono- 
basic acids they form but a single ether. 

They may be obtained synthetically, as well as by 
various indirect processes. 

Subjoined is a classified list of the more important 
monatomic alcohols: 

FIRST SERIES, 

C n H 2n + 2 0. 

Methyl alcohol (wood spirit), C H 4 O 
Ethyl alcohol, (spirit of wine) C 2 H 6 O 

Propyl alcohol - - C 3 H 8 O 

Butyl alcohol, - - - C 4 H 10 O 

Amyl alcohol, - - C 5 H 12 

Setyl alcohol - - - C 6 H 14 

Octyl alcohol - - C 8 H 18 

Sexdecyl alcohol - - - C^H^ O 

Ceryl alcohol - - C 27 H 56 O 

Myricyl alcohol - - - C 30 H 62 O . 

SECOND SERIES, 

C n H 2n O. 

Yinyl alcohol - - C 2 H 4 O 

Allyl alcohol - - - C 3 H 6 0. 

THIRD SERIES, 

C n H 2n _ 2 0. 
Borneol alcohol - - C 10 H 18 O. 



46 ORGANIC CHEMISTRY. 



FOURTH SERIES, 




C n H 2n _ 6 0. 




Benzyl alcohol 


C 7 H 8 


Xylyl alcohol 


C 8 H 10 O 


Cumol alcohol 


C 9 H 12 


Cymol alcohol 


- C 10 H u O 


FIFTH SERIES, 




C n H 2n _80. 




Cinnyl alcohol 


C 9 H 10 O 


Cholesteryl alcohol 


- C 26 H^O 



MoNATOMIC ALCOHOLS HAYING THE GENERAL FORMULA, 

C n Ii 2n+2 0. 

METHYL ALCOHOL, OR WOOD-SPIRIT. 

CH 4 = C ^ 3 1 O. 

This substance is found in the liquid obtained on 
distilling wood. The distillate contains in addition, 
water, acetic acid, tar, and various oils. In order to 
extract the methyl alcohol, it is again distilled and 
that portion which passes over at 90° is collected ; this 
is diluted with water, the oil which precipitates sepa- 
rated, and the liquid agitated for a considerable time 
with olive oil. This oil is then removed, the liquid 
redistilled several times and only that portion collected 
which passes over above 70°. On being again 



ALCOHOLS. 47 

distilled with calcium chloride it furnishes methyl al- 
cohol, nearly pure, boiling at 66.5°. 

There are other methods of rectifying besides the 
one here given. 

This body possesses most of the general properties 
of ordinary alcohol. Under the action of the oxides it 
furnishes an aldehyd and formic acid. 

Witih the acids it produces ethers; viz., with 

PIT I 

hydrochloric acid, methyl chloride, CH 3 C1= ™ 3 f 5 

with acetic acid, 

"R j 
methyl acetic ether, C 3 H 6 2 =p Tin \® m 

Chloroform, CHC1 3 . 

Methyl chloride produces with chlorine a regular 
series of products of substitution. One of these terms, 
CHC1 3 , is the very important body, chloroform, dis- 
covered in 1831 by Soubeiran and Liebig. 

To prepare this compound, 40 litres of water, 5 kilos 
of recently slacked lime, and 10 kilos of chloride of 
lime are heated to 40°; 1500 grams of 90 per cent, 
alcohol are then added and the retort luted with clay. 

It is now heated for a moment to the boiling point 
and the fire then at once slackened. 

The ebullition having ceased there will be found two 
layers in the receiver. The upper layer is formed of 
water and alcohol, the lower one is chloroform nearly 
pure. The latter is washed with water, agitated with 
a dilute solution of potassium carbonate, or with fused 



48 ORGANIC CHEMISTRY. 

calcium chloride for twenty-four hours, and distilled 
to four-fifths. 

Chloroform is a colorless liquid. When first pre- 
pared it has a sweetish penetrating taste, and an agree- 
able, ethereal odor. 

Its density is 1.48; it boils at 60.5°, is soluble in 
alcohol and ether and difficultly so in water. 

It burns, though not readily; its flame having a 
green margin. It dissolves iodine, sulphur, phos- 
phorus, fatty substances and resins. 

An alcoholic solution of potassa decomposes it into 
chloride and formiate : 

CHC1 3 + 4KHO = 3KC1 + CHK0 2 + 2H 2 0. 
Physiological Action. 

Chloroform is at present very generally used as an 
anesthetic. Opinions as to its manner of acting are 
divided. Formerly it was thought that the insensi- 
bility produced was the commencement of asphyxia. 
Since then it has been ascertained that the heart, in 
case of poisoning by chloroform, immediately loses all 
power of contraction, and it is now generally admitted 
that paralysis of the muscles and nerves of the heart is 
produced. 

As the vapor of chloroform is very dense, care should 
be taken that in its use, access of air to the lungs be 
not wholly prevented, or serious consequences may re- 
sult. Probably the fatal accidents that have occurred 



ALCOHOLS. 49 

may, in some instances at least, be attributed to lack 
of care in this regard. 

It is of great importance that the chloroform used 
should be quite pure. In some cases it has been found 
to have undergone spontaneous decomposition after 
exposure to a strong light. It ought to communicate 
no color to oil of vitriol when agitated with it. The 
liquid itself should be free from color or any chlorous 
odor. When a few drops are allowed to evaporate on 
the hand no unpleasant odor should remain. 

Shuttleworth (100, 4, 339) states that partially de- 
composed chloroform can be rectified by agitating it 
with a solution of sodium hypo-sulphite. 



OKDINAKY ALCOHOL. 

Ethtlic, ok Yinic Alcohol. 

Formula: C2H 6 0. 
Density of vapor 23. 
Density .81. 
Boils at 78.4o. 
Cannot be solidified. 

It is prepared by the fermentation of saccharine 
liquids at a temperature of 25° to 30°, in the presence 
of a small quantity of a ferment. Cane sugar does 
not directly, become alcohol under the influence of a 
ferment. It is first transformed into two other sugars, 
glucose and levulose. 



50 ORGANIC CHEMISTRY. 

C 12 H 22 O n + H 2 0=C 6 H 1 A+C 6 H 1 o - 6 . 

Glucose. Levulose. 

In its final fermentation nearly all the sugar is 
changed into alcohol and carbon dioxide, 

C 6 H 2 G =2C 2 H 6 0+4C0 2 . 

This equation accounts for the transformation of 94 
to 96 per cent, of the sugar employed, but besides 
alcohol and carbon dioxide, succinic acid is always 
formed as well as glycerine, and in most cases " fusel 
oil," consisting chiefly of amyl alcohol. 

Fermentation is a phenomenon correlative with the 
development and growth of cells of the fungus My co- 
derma (Torula) cerevisice which constitutes yeast. 
Sometimes the sugar is furnished as a natural product 
by fruits ; often glucose is produced from the starch 
of cereals, potatoes, etc., and then changed into alcohol 
afterwards. Corn is the leading original source in 
this country. 

Alcohol obtained by fermentation is concentrated 
by distillation. This operation is performed in retorts, 
the construction of which is based upon a principle 
developed by A. de Montpellier, and improved by 
Derosne, Dubrunfaut and others. The object is to 
prevent the distilling over of the water with the alco- 
hol, and is quite well accomplished by the improved 
methods now employed. The details are not suited 
to the scope of this work. 

The application of this rational method of distilling 



ALCOHOLS. 51 

admits of obtaining liquids containing xip to 90 per 
cent, of alcohol, but it is difficult to go beyond that 
point of concentration. 

In order to prepare alcohol more concentrated, sub- 
stances having a great avidity for water must be used. 
Calcium chloride is not suitable, as it unites with 
the alcohol. Anhydrous sulphate of copper, carbon- 
ate of potassium or quicklime do not produce absolute 
alcohol. But it is very rare that perfectly anhydrous 
alcohol is required. Alcohol of 97 per cent, is obtained 
in treating alcohol of 85 per cent, during two days with 
lime, or better, with a sixth or seventh part of its weight 
of dry potassium carbonate, and then distilling. If it 
is desired to procure absolute alcohol, very concen- 
trated alcohol is treated with caustic baryta until the 
liquid is colored yellow and then distilled. 

Alcohol in fresh bread made with yeast has been 
found by Bolas (8-27-271) to the amount of .314 per 
cent. Slices of bread a week old contained .12 to .13 
per cent. 

Absolute alcohol is a colorless liquid, more limpid 
than water, of an agreeable odor and a burning taste. 
It boils at 78.4°, is neutral, combustible and burns 
with a flame but little luminous. It heats on coming 
in contact with water, and attracts the moisture of the 
air very rapidly. 

It contracts upon mixing with water; the max- 
imum of contraction takes place at a temperature of 
15° when 52.3 vol. of absolute alcohol are mixed 
with 47.7 vol. of water; instead 100 vol. one obtains 



20 per 


cent 


14 to 16 




75 to 12 




10 to 12 




10 to 16 




2 to 1 




1 to 8 





b2 ORGANIC CHEMISTKY 

96.3 vol. At the moment of admixture numerous 
air bubbles escape and the mixture becomes heated. 

The alcoholic strength of the liquids consumed as 
beverages varies considerably. 

Madeira wines, about 

Malaga " 

Bordeaux " " 

Khine " " 

California " " 

Cider " " 

Beer " " 

Spirits are distilled from fermented liquids; hrandy 
from wine ; whisky from a mash of corn or rye ; rum 
from molasses, etc. They contain about 50 per cent, 
of alcohol. 

The term proof spirits was originally given to al- 
cohol sufficiently strong to fire gunpowder when 
lighted. The strength of proof spirits now varies in 
different localities, and it would be well were this 
ambiguous designation no longer employed. 

Alcohol dissolves the caustic alkalies, certain ni- 
trates, chlorides and other salts, also various gases. 
With some of these, genuine chemical combinations 
are produced, and not mere solutions; this is the case 
with calcium chloride and magnesium nitrate. 
Alcohol can be mixed with ether in all proportions; 
it dissolves the resins, essential oils, and a great num- 
ber of other organic bodies. 

The chemical properties of alcohol are very inter- 



ALCOHOLS. 53 

esting. Vapor of alcohol is decomposed on passing 
through a tube heated to redness; hydrogen, marsh- 
gas, oxide of carbon, small quantities of naphthalin, 
benzol, and phenol are formed. In presence of air 
and water it slowly oxidizes and yields acid com- 
pounds. This action is rapid, if a hot spiral of plati- 
num is placed in the alcoholic vapor. 

Experiment. — Place a small platinum spiral in the 
wick of an alcohol lamp, light and theu blow out the 
flame. It will be seen that the spiral remains incan- 
descent. Spongy platinum acts still more energetically; 
if very concentrated alcohol is poured drop by drop into 
a capsule containing spongy platinum, or platinum 
black, it will be seen to redden, fumes are produced and 
an acid liquid is formed containing chiefly aldehyd 
and acetic acid. The same oxidation occurs if diluted 
alcohol is exposed to the air in the presence of mother of 
vinegar, a cryptogamic plant, (Mycoderma aceti). In 
fact, this is the basis of the manufacture of wine-vin- 
egar and alcohol. 

Fuming nitric acid reacts upon alcohol with ex- 
plosive energy. Aldehyd is formed, also acetic ether, 
nitrous ether and acetic, formic, gly collie, oxalic and 
carbonic acids. Alkaline hydrates attack alcohol even 
in the cold potassium acetate being the chief product 
formed. If alcoholic vapor is made to pass over lime 
heated to 250°, hydrogen gas and calcium acetate 
are produced; the latter is decomposed at a more 
elevated temperature into marsh gas and water. If 
silver or mercury is dissolved in nitric acid, and 
90 per cent, alcohol added to the cooled solutions, a 



54 ORGANIC CHEMISTRY. 

lively ebullition results, and a crystalline precipitate is 
deposited which explodes at 185°, or by percussion. 
This body is the fulminate of silver or mercury, re- 
spectively, which is considered as derived from methyl 
cyanide, CH 3 Cy, by the substitution of 1 molecule of 
nitryl, and of 1 atom of mercury, or 2 of silver for 3 
atoms of hydrogen. The formulae are C(N0 2 )HgCy; 
C(N0 2 )Ag,Cy. 

Potassium attacks absolute alcohol, and is dissolved 
liberating hydrogen; on cooling, potassium ethylate is 
deposited. Sodium acts in the same manner. These 
compounds, if brought in contact with water, regenerate 
alcohol and the respective alkaline hydrates. 

Acids attack alcohol and furnish compound ethers, 
which we will study later. Ozone, according to A. W. 
Wright, (80 — 1_3]7 — 181) oxydizes alcohol to acetic acid. 

Physiological Action of Alcohol. Uses of Al- 
cohol. — Alcohol coagulates the blood; injected into the 
veins it produces instantaneous death. It is a very 
powerful poison, as are all alcohols of the series 
CnH^O. Rabuteau (9 — 81 — 631) has shown that 
they are more poisonous in proportion as their mole- 
cules are complex. Cases have been observed where a 
large dose of alcohol has caused death in half an hour. 

The worse than worthless character of distilled 
liquors as beverages is no longer an open question. 
With regard to their value as food or medicine, a more 
authoritative or competent expression of opinion can- 
not be desired than that of the International Medical 
Congress, which at its session in Philadelphia in 1876, 
said: 



ALCOHOLS. 55 

"1. Alcohol is not shown to have a definite food 
value by any of the usual methods of chemical analy- 
sis or physiological investigation. 

" 2. Its use as a medicine is chiefly that of a cardiac 
stimulant, and often admits of substitution. 

" 3. As a medicine, it is not well fitted for self-pre- 
scription by the laity, and the medical profession is 
not accountable for such administration, or for the 
enormous evils arising therefrom. 

" 4. The purity of alcoholic liquors is, in general, 
not as well assured as that of articles used for medicine 
should be. The various mixtures when used as medi- 
cine, should have definite and known composition, and 
should not be interchanged promiscuously." 

The dissolving power of alcohol renders it very ser- 
viceable in the arts. Solutions in this menstruum are 
called alcoholic tinctures. Only the purest alcohol 
ought to be used in pharmacy, though of course, various 
strengths are requisite, as it should be of a degree to 
suit the nature of the matter to be dissolved. If the 
substance to be treated is a resin, or some substance 
absolutely insoluble in water, a very concentrated alco- 
hol is preferable. A weaker alcohol is made use of, if 
the matter is one that is soluble, both in alcohol and 
water. 

Alcohol acts not only as a solvent, but also as a pre- 
ventative of decay. This is a property which renders 
it especially valuable in the preparation of remedies. 



56 ORGANIC CHEMISTRY 

AMTL ALCOHOL. 
C 3 H 12 = C 5 H„ 



H 

Synonyms: Fotjsel (oe Fusel) Oil, Potato Spieit. 

The amylic compounds derive their name from 
Amylum, starch, the chief constituent of the potato. 
They are formed in some proportion in almost every in- 
stance of alcoholic fermentation of sugar. Amylic 
alcohol is usually prepared on fractionally redistilling 
the oil which remains when the alcohol, prepared 
from potatoes, barley, corn, etc. , is distilled. The pro- 
duct which comes over at 132°, is that collected. 
Cahours and Balard first established the analogy, in 
constitution and properties, of this compound with 
ordinary alcohol. It is a monatomic alcohol, giving 
with oxidizing re-agents, valeric acid. 

C 5 H 12 0+0 2 = C 5 H 10 O 2 +H 2 O, 



Amylic alcohol. Valeric acid. 

and with acids, compound ethers, as 

Chloride of amyl, C 5 H n Cl. 

Acetate of amy] or amyl-acetic ether, n 5 ^ 1 /! r ®' 



ALCOHOLS. 57 

MONATOMIC ALCOHOLS. 

Having the general Formula C n H 2n O. 

Allylic Alcohol, C 3 H 6 === C§H 5 ) n 

H f U * 

This is a body giving the same reactions as ordinary 
alcohol. The radicle it contains is the same as that 
in the triatomic alcohol, glycerine. Among its deriva- 
tives there are two which are of considerable impor- 
tance : 

Allyl sulphide, ^ 5 i S. 

Sulpho-cyanide, C^ \ ®' 

The former is oil of garlic; the latter oil of mustard. 
Oil of garlic is prepared by the following method: 
allylic alcohol is treated with phosphorus iodide which 
furnishes allyl iodide C 3 H 5 I. This iodide is afterwards 
mixed with an alcoholic solution of potassium sulphide 
and the whole is distilled; the product which passes 
over is identical with the essential oil obtained in dis- 
tilling garlic, onions, assafoetida, etc., with water. 

OIL OF MUSTARD, OR SULPHO-CYANIDE OF ALLYL. 

This body is prepared by causing iodide of allyl to 
react upon potassium sulpho-cyanide, xr f S, and may 

be regarded as sulpho-cyanic acid, o f S, having the 



58 ORGANIC CHEMISTRY. 

hydrogen replaced by the radicle of allyl alcohol, C 3 H 5 . 
The product which distills over is an irritating liquid 
which boils at 145°, like the oil prepared from mus- 
tard directly. This substance may also be obtained 
by the action of allylic alcohol upon potassium sul- 
pho-cyairide. It is likewise obtained by the fermenta- 
tion of mustard seeds. 

Sulpho-cyanide of allyl does not exist already formed 
in black mustard (Sinapis nigra), but according to 
Bussy, its formation is due to a particular ferment. 

Oil of mustard combines directly with ammonia, 
forming a crystalline substance called thiosinnamine, 
C 4 H 8 N 2 S, which, in contact with mercuric oxide, 
changes into an alkaloid called sinnamine, of which 
the composition is C 4 H 6 N 2 . It reacts upon lead oxide 
producing a substance called sinapoline whose formula 

is c 7 H 12 ]sr 2 o. 

BORNEO CAMPHOR, OR BORNEOL C 10 Hi 8 O. 

This body exudes from the Dry obalcmops camphor a 
(Borneo). It is crystalline and has an odor between 
that of camphor and pepper. It fuses at 195°, and 
boils at about 220°. It is dextrogyrate. Heated with 
nitric acid it furnishes common camphor C 10 Hi 6 O. 

DIATOMIC ALCOHOLS OR GLYCOLS. 

Ordinary Glycol, (C S H 4 ) — 3 — H 3 =C 3 H 6 3 
Propyl " (C 3 H 6 ) _0 2 -H 2 =C 3 H 8 2 





ALCOHOLS. 


Butyl Glycol, 
Amyl 

Hexyl " 
Octyl 


(C 4 H 8 )-O 3 -H 3 =C 4 H 10 O 3 
(C 5 H 10 )-O 3 -H 3 =C 5 H 12 O 2 
(C 6 H 12 )-0 2 -H 2 =C 6 H 14 2 
(C 8 H 16 )— 2 — H 2 =C 8 H 18 2 



59 



TRIATOMIC ALCOHOLS. 

Glycerine, (C 3 H 5 )-0 3 -H3=C 3 H 8 03. 

TETRATOMIC ALCOHOLS. 

Erythrite, (C 4 H 6 )— 4 — H 4 =C 4 H 10 O 4 . 

OTHER COMPLEX ALCOHOLS. 

Glucose and its isomerides, (C 6 H 6 ) — 6 — H 6 =C 6 H 12 6 . 
Mannite, - - (C 6 H 8 )— 6 — H 6 =C 6 H 14 6 . 

Dulcite, - - - (C 9 H 8 )-0 6 -H 6 -C 6 H 14 6 . 

ORDINARY GLYCOL. 

C 2 H 6 2 =( C g 2 }0 2 . 

The discovery of the glycols was an event of 
great importance. It was achieved by Wurtz in 1856, 
and the glycol of which we are treating was the first 
discovered. 

In a flask surmounted by a condenser, two parts of 
potassium or sodium acetate, are dissolved in weak 
alcohol and one part of ethylene bromide added. This 



60 ORGANIC CHEMISTRY. 

mixture is heated in a water bath as long as the pre- 
cipitate of alkaline bromide continues to form, care 
being taken at the same time to keep the worm well 
cooled, in order that the vapors of alcohol may contin- 
ually now back into the flask. The alcohol is* distilled 
off in a water bath, and the residue afterwards also 
distilled at a higher temperature, and that part col- 
lected which passes over between 140° and 200° . This 
portion which contains monacetic glycol, is heated 
with a saturated solution of baryta until the liquid 
acquires a strong alkaline reaction. The excess of 
baryta is removed by passing carbon dioxide through 
the solution which is then filtered and evaporated. 
The barium acetate is precipitated completely by strong 
alcohol, and the alcohol subsequently removed by dis- 
tillation. The retort is now heated in an oil bath, and 
that portion set aside which boils above 150° . This is 
redistilled and the distillate between 190° and 198° 
is the product sought. Zeller and Huefner have lately 
(18, 10,270) obtained the purest glycol by simply heat- 
ing a solution of potassium carbonate with ethylene 
bromide. 

Glycol is a colorless, odorless liquid, somewhat 
viscid and having a sweetish taste. Its density is 
1.12; water and alcohol dissolve it in all proportions. 
Ether dissolves it with difficulty. 

It is not oxydized in the air under ordinary con- 
ditions, but if dilute glycol be made to fall on plati- 
num black, it becomes heated and is transformed into 
gly colic acid. Its equivalence is shown by the follow- 



ALCOHOLS. 61 

ing : glycol attacks sodium forming two sodium 
glycols; 



C 2 H 4 ) n C 2 H 4 ) n 

JSTaH | U2 ' NaJ 2 * 



These glycols furnish two ethyl glycols on being 
heated with ethyl iodide. 

C2H4 \ r\ C 2 H 4 ) ^ 

C 2 H 5) Hf°^ (0 2 H 5 ).J° 2 - 

Ethyl-glycol. Diethyl-glycol. 

"With hydrogen bromide it furnishes two different 
products according to the number of molecules of HBr 
taken. 



C 2 H 6 2 + HBr = C 2 H 5 BrO + H 2 0. 



Monobromhydric 
ether. 



C 2 H 6 2 + 2HBr=C 2 H 4 Br2f 2H 2 0. 



Ethylene 
bromide . 



It is evident that mixed ethers may be obtained by 
treating glycol not with two molecules of the same 
acid, but with two molecules of different acids. Thus 

O TT ) 
aceto-chlorhydric glycol is formed ,p tt Q\pi 4 r O. 



62 ORGANIC CHEMISTRY. 

These ethers, in the presence of alkalies, are re- 
formed into their respective acids and glycol, in the 
same manner in which ethers of ordinary alcohol 
regenerate alcohol. 

Monochlorhydric and aceto-chlorhydric glycol form 
an exception to this rule ; they form oxide of ethylene 
in presence of alkalies. 

OXIDE OF ETHYLENE, C 2 H 4 0, 

a polymer of (CalX^C^, is related to glycol as ordinary 
ether to alcohol. It is not obtained like the latter by the 
action of hydrogen sulphate on the alcoholic compound, 
but is produced by the action of potassa on mono- 
chlorhydric glycol. A solution of potassa is gradually 
poured into chlorhydric glycol placed in a glass, or a 
tubulated retort. 

KHO + C 2 H 5 C10 = KC1 + H 2 + C 2 H 4 0. 

The oxide of ethylene distills over with the water; 
the latter is absorbed by causing the vapors to pass 
through a flask containing anhydrous calcium chloride, 
and the oxide is condensed in a receptacle placed in a 
refrigerating mixture. 

It is a colorless, ethereal, fragrant liquid; boiling at 
13°. Its density is 0.89. Ethylene oxide is very solu- 
ble in water, alcohol and ether. It burns with a lumin- 
ous flame and reduces silver salts. It has the compo- 
sition but not the properties of aldehyd, of which it is 
an isomeride. 



ALCOHOLS. 63 

Oxide of ethylene is a very remarkable body. It 
combines directly with oxygen, hydrogen, chlorine and 
bromine, also combines directly with acids, often even 
with the disengagement of heat, forming the ethers of 
glycol and polyethylenic alcohols. This body is there- 
fore a true non-nitrogenous basic oxide. 



64 ORGANIC CHEMISTRY. 



TKIATOMIC ALCOHOLS OE GLYCEEDTES. 
Ordinary Glycerine, C 3 H 8 3 = 3 tt 5 [ O, . 

This body, discovered by Scheele, in 1779, and 
called by him, on account of its sweet taste, the sweet 
principle of oils, has been specially studied by Chevreul 
and by Pelouze. Berthelot discovered its real nature 
and proved it to be a tri atomic alcohol. 

Glycerine is prepared by decomposing neutral 
fatty bodies, in the soap and candle industry by alka- 
lies, or better still by superheated steam. {TilghmarCs 
process.) It is obtained in pharmacy, whenever lead 
plaster is prepared and remains in the water with 
which the latter is washed. 

It is much employed in pharmacy and perfumery 
and as a solvent for many substances. Crude glycer- 
ine may be purified by boiling with animal charcoal 
and filtering before being evaporated to the required 
consistency. The best process consists in distilling the 
crude condensed glycerine in a current of steam. Pas- 
teur has shown that glycerine is produced in a very 
small quantity in alcoholic fermentation. We owe to 
"Wurtz, a remarkable synthetical reproduction of glycer- 
ine. Propylene C 3 H 6 furnishes an iodide C 3 H 5 I, called 
iodide of allyl. This body produces with bromine the 



ALCOHOLS. 65 

compound C 3 IL;Br 3 which, treated with potassa, or 
oxide of silver, yields glycerine. 

C 3 H 5 Br 3 +3KHO = 3 KBr.+C 8 H 8 8 . 

Glycerine . 

Glycerine is a syrupy liquid, colorless, of a sweetish 
taste and destitute of odor; its density is 1.28 at 15°. 
Sarg has obtained crystals of glycerine, whose angles 
have been measured by Victor Lang (2-152-637). 
They are rhombic in form and very deliquescent. Glyc- 
erine is soluble in alcohol and water in all propor- 
tions; it is not dissolved by ether. It dissolves alka- 
lies, alkaline sulphates, chlorides and nitrates, copper 
sulpnate, silver nitrate and many other salts. 

Glycerine distills at 280°, but is thereby partially 
decomposed. It may, however, be distilled in a 
vacuum without change. It is decomposed at a tem- 
perature above 300°, and oils, inflammable gases, 
carbon dioxide, and a product very irritating to the 
eyes, called acrolein* acrylic aldehyd, are formed; 
this last substance may be obtained pure by distilling 
glycerine with, sulphuric, or phosphoric acid. The 
formula of acrolein is C 3 H 4 2 ; it is also produced in 
the dry distillation of all fatty bodies which contain 
glycerine. If glycerine be made to fall drop by drop 
upon platinum black, it unites, like alcohol and 
glycol, with 2 and glyceric acid is formed. 

C 3 H 8 3 + O a =C 8 H 6 4 + H 2 0. 

The oxidation of the glycerine does not stop here; 



66 ORGANIC CHEMISTRY. 

there is subsequently formed, acetic, formic, and car- 
bonic, but chiefly oxalic acid. The action of acids on 
glycerine demonstrates two facts; first, that glycerine 
is an alcohol; second, that it is a triatomic alcohol. 
On treating glycerine with hydrochloric acid the first 
reaction is similar to that between alcohol and this 
acid, 

HC1+C 3 H 8 3 =C 3 H 7 C10 2 +H 2 0. 

Monochlorhydric ether, 
or 
Monochlorhydrin. 

The continued action of phosphorous perchloride 
upon glycerine, or the dichlorhydrate of glycerine, 
effects the elimination of additional molecules of water 
and the formation of trichlorhydrin. 

3HC1+C S H 8 3 =C 8 H 5 C1 S + 3(H 2 0). 

Trichlorhydrin. 

Berthelot has studied the acetines. butyrines (tri- 
butyrine exists in butter), valerines, and many other 
ethers of glycerine. If glycerine is mixed with cold 
nitric acid, and sulphuric acid added drop by drop, an 
oily substance separates out which is tr dnitro glycerine, 
C 3 H 3 (]^Oo) 3 3 . This body detonates with great vio- 
lence. It acts very energetically on the system. A 
few drops placed on the tongue produce violent me- 
grim. Glycerine forms compounds with lime anal- 
ogous to those formed by sugar, according to P. Car- 
les, (1-174-87). 



ALCOHOLS. 67 

Uses. — The uses of glycerine in the arts, and 

especially in pharmacy, are numerous and important, 
many of which are based upon the solvent power of 
this compound. Henry Wurtz (31-195-58) has made 
valuable suggestions as to its economical applications. 

TABLE SHOWING THE SOLUBILITY OP SOME CHEMICALS IN GLYCERINE, (FROM 

KLEVER.) ONE HUNDRED PARTS OP GLYCERINE DISSOLVE THE ANNEXED 

QUANTITIES OP THE FOLLOWING CHEMICALS: 

Arsenous oxide, 20.00 

Arsenic oxide, 20.00 

Acid, benzoic, 10.00 

" oxalic, 15.00 

" tannic, 50.00 

Alum, 40.00 

Ammonium carbonate, 20.00 

" chloride, 20.00 

Antimony and potassium tartrate, 5.50 

Atropia, 3.00 

Atropia sulphate, 33.00 

Barium chloride, 10.00 

Brucia, 2.25 

Cinchonia, 0.50 

" sulphate, 6.70 

Copper acetate, 10.00 

" sulphate, 30.00 

Iron and potassium tartrate, 8.00 

" lactate, 16.00 

" sulphate, 25.00 

Mercuric chloride, 7.50 

Mercurous chloride, 27.00 

Iodine, 1.90 

Morphia, 0.45 

Morphia acetate, 20.00 

" chlorhydrate, 20.00 

Phosphorus, 0.20 

Plumbic acetate, 20.00 

Potassium arsenate, 50.00 

" chlorate, 3.50 

" bromide, 25.00 

" cyanide, 32.00 

" iodide, 40.00 

Quinia, 0.50 

" tannate, 0.25 



68 ORGANIC CHEMISTRY. 

Sodium arsenate. 50.00 

" bicarbonate, 8.00 

" borate, 60.00 

" carbonate, 98.00 

41 cblorate, 20.00 

Sulpbur, 0.10 

Strychnia, 0.25 

" nitrate, 4.00 

" sulphate, 22.50 

Urea, 50.00 

Veratria, 1.00 

Zinc chloride, 50.00 

" iodide, 40.00 

" sulphate, S5.00 



ETHERS* 69 



ETHERS. 

SIMPLE ETHEKS. 

Ethers are products formed by the action of alcohols 
upon acids. 

By most chemists they are looked upon as referable 

to the oxides of metals ; thus p-rr 3 [ O and p 2 -rr 5 [ O, 

may be regarded as the oxides respectively of methyl 
and ethyl. They bear the same relation to alcohols 
that oxides of the metals do to the hydrates. 

Potassium hydrate KOH. 

Ethyl hydrate, or ethyl alcohol C 2 H 5 OH. 

Potassium oxide ^ I 0. 

Ethyl oxide or ethyl ether ^ 2 ^ 5 l O. 

The simple ethers are mostly liquid. They are very 
slightly soluble in water, while they are readily soluble 
in alcohol. Exposed to the action of alkaline solu- 
tions they regenerate alcohol. 

C 4 H 8 2 +KHO = C 2 H 6 0+KC 2 H 3 2 . 



70 OKGANIC CHEMISTRY. 

ETHYL ETHER. 

Synonyms : Vinic ether, sulphuric ether, common ether. 

Density .736. 
Density of vapor, 37. 
Specific gravity of vapor, 2.586. 
Boiling point, 35.5°. 

To prepare this compound, sulphuric acid is heated 
with alcohol in a retort, placed in a sand-bath. The 
ether distills, its vapor being received in a well cooled 
condenser, provided with a long tube which conducts 
the uncondensed vapor into a chimney. 

The cork adapted to the tubulure of the retort is 
provided with two openings ; in one is fixed a ther- 
mometer, through the other a tube passes which fur- 
nishes the supply of alcohol. All the connections 
should close perfectly. When the apparatus is arranged 
in this manner, pour TOO grams of 85 percent, or 90 per 
cent, alcohol into the retort, and add, little by little, 100 
grams sulphuric acid of 1.84 sp. gr., then heat. When 
the thermometer attains 130°, cause the alcohol to 
flow from the upper vessel at a rate sufficient to keep 
the temperature between 130° and 140°. The weight 
of alcohol capable of being transformed into ether is 
from 13 to 15 times the weight of the mixture first in- 
troduced into the retort. The distilled liquid is mixed 



ETHEKS. 71 

with 12 parts, to every 100 of its weight, of a solution 
of soda having a specific gravity of 1.32, and agitated 
from time to time, during 18 hours. 

The ether is decanted by means of a glass siphon, 
redistilled and four-fifths of the liquid collected. The 
remainder may serve for a future operation. 

This furnishes ordinary ether. To further purify, 
wash with water, decant and treat for two days with equal 
parts of quick lime and fused calcium chloride. "Wil- 
liamson has clearly shown that etherification takes 
place in two stages or successive reactions as follows: 

C 2 H 6 + H 2 S0 4 = H 2 + (C 2 H 5 )HS0 4 . 

Ethylsulphuric acid. 

(C 2 H 5 )HS0 4 + C 2 H 6 = C 4 H 10 O + H 2 S0 4 . 

This explains how a small quantity of sulphuric 
acid etherizes a large amount of alcohol, since sul- 
phuric acid is constantly regenerated. This is con- 
firmed by the following experiment. Iodide of ethyl 
is made to react upon potassium alcohol ; ether is 
obtained as indicated by the reaction; 

C 2 H 5 I + C 2 H 5 OK = C 4 H 10 O + KI. 

Ether is a neutral, volatile liquid, colorless, having a 
burning taste and a strong agreeable odor. When 
agitated with water it rises to the surface, but the 
water dissolves about one ninth of its own weight of 
the ether. It is miscible with alcohol in all propor- 



72 ORGANIC CHEMISTRY. 

tions and with wood spirit. Ether is frequently adul- 
terated with the latter substance. Next to alcohol it 
is the most generally employed solvent for organic 
substances. It dissolves resin, oils and most com- 
pounds rich in carbon and hydrogen. 

Bromine, iodine, chloride of gold and corrosive sub- 
limate are soluble in this liquid. It dissolves phos- 
phorus and sulphur in small quantity. 

"W. Skey (8 — Aug. 3, '77,) has shown that contrary to 
the usual statement in standard works, ether dissolves 
notable quantities of the alkalies. 

At a red heat it is decomposed and furnishes carbon 
monoxide, water, marsh gas and acetylene. 

It is exceedingly inflammable, and burns with a 
bright flame. 

Its extreme volatility, the density of its vapor, its 
insolubility in water and its great inflammability render 
its use dangerous, and explosions caused by it are of 
frequent occurrence. It should never be brought near 
a fire or light in open vessels. In case ether inflames, 
it is best, if possible, to at once close the vessel con- 
taining it, and thus avoid the more serious conse- 
quences ensuing from an explosion. Exposed to the 
air it experiences a slow combustion as in the case of 
alcohol, and the same compounds are the result. 

Chlorine acts violently upon it; in moderating the 
action, the whole or a part of the hydrogen may be 
replaced atom for atom by chlorine. 

Uses. — It is used in pharmacy in preparing etherial 



ETHEES. 73 

tinctures, and as an antispasmodic and stimulant in 
the well-known Hoffmann's anodyne. Its most impor- 
tant use in medicine is as an anesthetic, than which 
none is safer or more reliable in efficient hands. It 
is extensively employed in the laboratory and in 
photography. 

COMPOUND ETHEES 

are bodies built up on the type of water, having one 
half the hydrogen replaced by a hydrocarbide and the 
other half by a compound radicle containing oxygen, 
or, in other words, by the radicle of an acid. 

(OHO ) n 

ACETIC ETHER, )p tr Q\ \ O. 

To prepare this ether 8 parts of very concentrated 
alcohol are distilled with 7 parts of sulphuric acid and 
10 parts of anhydrous sodium acetate, which may be 
replaced by 20 parts of dry lead acetate. The distil- 
late is agitated with a solution of calcium chloride 
containing milk of lime, decanted, dried over calcium 
chloride and finally distilled. 

Seven parts of water dissolve one part of this body. 
Alcohol and ether dissolve it in all proportions. It 
is a solvent for many organic bodies. It is easily de- 
composed on contact with water. Potassa also effects 
this decomposition very readily. A prolonged action of 
ammonia transforms it into acetamide and alcohol. 



74 ORG-AXIC CHEMISTRY. 

OXALIC ETHEES. 

Oxalic acid, being a bibasic acid, furnishes with 
alcohol two combinations, one being acid and capable 
of combining with bases ; the other is neutral. C.H :0 O 4 . 

Only the latter is of interest. It may be prepared 
by introducing four parts of 90 per cent, alcohol and 
four parts of oxalic acid into a retort, adding to this 
mixture three to six parts of sulphuric acid and then 
rapidly distnling ; the product is washed several times. 
dried, then redistilled, collecting only the liquid which 
passes over at 184°. This ether is aromatic, oily, and 
gradually decomposes in water. 

Potassium changes it into carbonic ether. 

If oxalic ether is agitated with ammonia, a white 
powder, oxamide. and ethyl alcohol are produced. 

(CoH 5 \ j , N ^ rr 2 _ 



H 



Oxamide may be considered as derived from two 
molecules of ammonia, and belongs to a class of bodies 
called d (amides. 

It is a white substance, insoluble in cold water and 
alcohol. Heated with mercuric oxide it is transformed 
into carbon dioxide and urea. (Williamson.) 



ETHERS. 75 

Oxalic ether treated with ammonia in solution in 
alcohol furnishes oxamic ether. 

In this connection the compounds of the organic 
radicles with the haloid elements are usually studied: 
they are not unfrequently denominated ethers of the 
hydracids. Their type is a molecule of 

hydrogen, ^ I . 

CHLORIDE OF ETHYL OR CHLORHYDRIC ETHEK. 



,H 5 C1— C 2 H 5 

CI 



( 



This body is formed in small quantity when ethy- 
lene is made to react upon hydrochloric acid. 

To prepare it, alcohol contained in a flask sur- 
rounded by cold water, is saturated with hydrochloric 
acid gas and the mixture then distilled. 

C3H 6 0+HC1=C 2 H 5 C1+H,0. 

It is also obtained by pouring into a flask contain- 
ing 2 parts common salt, a mixture of 1 part alcohol, 
and 1 part sulphuric acid : it is then gently heated 
and the ether collected as previously shown. 

It is a liquid of an agreeable odor, and very volatile, 
having a boiling point of 12° and a vapor density of 
64°. A red heat decomposes it into ethylene and 
hydrochloric acid gas. It is combustible and burns 
with a green, smoky flame ; water dissolves the fif- 
tieth part of its volume, alcohol dissolves it completely. 



76 ORGANIC CHEMISTRY. 

With chlorine it furnishes a complete and regular 
series of products of substitution which are not iden- 
tical, but isomeric with the chlorine products of 
ethene. 

Their formulae are: 



CgH 4 Cl 2 
C 2 H 3 C1 3 
CgH 2 Cl 4 
C 2 H CI, 

C 2 Cl 6 . 


2THYL OR HTD] 


C 2 H 5 I = C ^ 



i] 



is obtained on causing alcohol to react upon iodide of 
phosphorus; the action is violent with white phos- 
phorus, considerably less so with red phosphorus. 

Six hundred grams of concentrated alcohol are intro- 
duced into a retort with 140 grains of amorphous 
phosphorus, and to this mixture 450 grams of iodine 
are added. The distilling is carried nearly to dryness. 
The product, condensed in the receiver, is washed with 
water containing a little potassa ; afterwards with pure 
water. It is then dried over calcium chloride and 
again distilled. 

Iodide of ethyl is a colorless liquid. Its density is 
1.975. It becomes colored on exposure to light, being 
slightly decomposed ; it is again rendered colorless on 
agitating it with an alkaline solution, which absorbs the 



ETHERS. 77 

acid formed. It burns with a green flame, leaving a resi- 
due of iodine. Ammonium compounds in alcoholic, or 
aqueous solution, furnish ethylamine. This amine can 
be attacked in its turn by iodide of ethyl and yields 
diethylamine and oxide of tetrethylammonium. The 
knowledge of these reactions and their application to 
other iodides are the basis of a general mode for the 
preparation of organic bases originated by Hoffmann. 
Iodide of ethyl, unlike the chloride, is readily decom- 
posed by solutions of silver nitrate, giving a precipi- 
tate of silver iodide. 

(W + AgNO, = (C 2 H 5 ) N0 8 +Agl. 

CYANIDE OF ETHYL, OR CYANHYDRIC ETHER. 

C s H 5 N = 2 H 5 )_ 

This ether is obtained on distilling in an oil-bath 
1 part of potassium cyanide, with 1-5 part of an alkaline 
sulpho-vinate. To the product, redistilled in a bath of 
salt-water, nitric acid is slowly added in excess ; it is 
then subjected to another distillation. Finally, it is 
dried over calcium chloride, and that which passes over 
from 195° to 200° is collected on redistillation. 

Cyanide of ethyl is a colorless liquid of an alliaceous 
odor, boiling at 97?. 

Cyanide of ethyl is decomposed by potassium hy- 
drate; ammonia is produced, and the acid obtained 
corresponds with a higher homologous alcohol. 



78 ORGANIC CHEMISTRY. 

CK(0 2 H 5 ) + 2H 2 = JSTH 3 + C 3 H 6 2 . 



Propionic acid. 

M. Meyer observed some years ago, that if cyanide 
of silver is treated with iodide of ethyl, a liquid is 
formed, boiling at 82°, of an odor which is not that of 
ordinary cyanhydric ether. Gautier has shown that this 
is an isomeric body, and that there are two isomeric 
series of cyanhydric ethers. Hoffmann has given a dis- 
tinctive character to these bodies: under the influence 
of the alkalies they produce a fixed substance, but 
this is formic acid and not ammonia, and a volatile 
substance which is a compound ammonia. 

H ) 

CN(C 2 H 5 ) + 2H 2 0= CHA + C 2 H S } N. 
— H ) 

Formic acid. Ethylamine. 

Oegano-metallic Compounds. 

Iodide of ethyl attacks the metals and furnishes a 
class of bodies called organo-metalliG radicles. None 
of these bodies are found in nature. They are formed 
from the iodohydric ethers by the substitution of a 
metal for the iodine; 

Zn + 2(C 2 H 5 I) = (C 2 H 5 ) 2 Zn + ZnI 2 , 

2Sn + 2(C 2 H 5 I) = (C 2 H 5 ) 2 Sn + Snl 2 . 

Practically these metallic radicles are obtained by 
various reactions: 



ORGANO-METALLIC COMPOUNDS. 79 

1. By the action of the metal upon the iodide, for 
example; 

2C 2 H 5 I + Zn 2 =(C 2 H 5 ) 2 Zn + Znl 2 . 

In certain cases, with tin for instance, the reaction is 
not as distinct, and there is formed in addition to stan- 
nethyl iodide, stannethyl iodides variously condensed. 

2d. The metal is treated with another radicle; thus 
sodium-ethyl is prepared by the action of sodium 
upon zinc ethyl, 

(C 2 H 5 ) 2 Zn + Na 2 = Zn + 2C 2 H 5 ]Sra. 

3d. On decomposing a metalloid compound radicle 
with a metallic chloride, 

3ZnCl 2 +2(C 2 H 5 ) 3 P=3(C 2 H 5 )Zn + 2PC1 3 . 

4th. Stannethyl is obtained by plunging a plate 
of zinc into a soluble salt of this radicle: the radicle 
is precipitated in the form of an oily liquid. 

Cacodyl, As(CH 3 ) 2 was the first discovered of this class 
of bodies. It was obtained by Bunsen on distilling 
arsenous acid with potassium acetate. The organic 
radicles combine with metalloids with more or less 
energy ; zinc -ethyl and cacodyl take fire in the air ; 
they also decompose water. The products of oxida- 
tion vary with the nature of the compounds employed; 
zinc-ethyl furnishes the body, CJI 5 ZnO, zinc-ethyl- 
ate, which, in contact with water, produces alcohol and 
oxide of zinc. The metals which are less readily oxy- 



80 OEGAWIC CHEMISTEY. 

dized, such as tin, lead and mercury, give oxides 
which play the parts of bases, and these latter com- 
port themselves like the oxides of the metals they con- 
tain. Finally, the radicles formed by the elements, 
phosphorus, arsenic, and antimony, give, with oxy- 
gen, compounds which generally have the character of 
acids. 

Some of the organic derivatives containing phos- 
phorus are very complex. For instance, J. Auanoff 
(60-75-493) has obtained a body he denominates, 
methyldiethyljphosphoniuniphenyloxidehydrate! 

To prepare zinc-ethyl, we introduce into a flask 
connected with a condenser inclined in such a manner 
that the vapors find their way back into the flask, 100 
grams iodide of ethyl, 75 grams of zinc, and 6 to 7 
grams of an alloy of zinc and sodium, and heat in 
the water bath until the zinc is dissolved ; then the 
condenser is inclined as usual, and the distilling is 
effected over a direct fire, collecting the liquid pro- 
duct in a flask filled with dry carbon dioxide. 
Finally it is again distilled in this gas, and that col- 
lected which passes over from 116° to 120°. All the 
vessels and all the substances should be absolutely 
dry, and it should always be collected and distilled in 
vacuo, or in carbon dioxide. It is a colorless liquid, 
whose density is 1.182, boiling at 118°, inflammable 
on exposure to the air. 

With sodium this body furnishes sodium-ethyl, and 
with chloride of phosphorus or arsenic, it furnishes 
triethyl phosphine, P(C 2 H 5 ) 3 , and triethyl arsine, 
As (C a H 3 ) 8 . 



ETHERS. 81 

Mercury-methyl, treated with iodine, furnishes a 
hydro-carbide which has the formula of methyl, CH 3 . 

Professors Crafts and Friedel (72-[4]19-334) have 
prepared a large number of compounds of silicon with 
compound radicles, from which they have deduced 
valuable theoretical considerations. 

MISCELLANEOUS ETHEKS. 

Formic, butyric, valerianic ether, and other ethers 
of the fatty series are prepared in the same manner as 
acetic ether, and have the general properties of this 
ether. The odor of these ethers is agreeable. Bu- 
tyric ether has the odor of pine-apple, and valerianic 
ether that of pears ; cenanthylic ether has the aroma 
of wine, etc. They are used in the manufacture of 
syrups, flavoring extracts, and for imparting an odor 
to liquors. 

If the difference between the points of ebullition of 
these ethers is examined it will be seen that the 
addition of the elements. CH 2 causes an elevation of 
about 20° in the point of ebullition. Kopp has 
shown that this fact is a general one and applies 
to the alcohols, and acids of the same series, and to 
the homologous bodies in general. 

Point of ebullition. Difference. 
Formic ether, - - 55° 1QO 

Acetic " - - 74° i% 

Propionic " - - 95° ^ 

Butyric " - - 119° ~* 

Valerianic" - - 133° * 



82 ORGANIC CHEMISTRY. 

The boiling point of one of these bodies may accord- 
ingly be predicted, if that of one of its homologous 
substances is known. There is a certain close relation 
between the point of ebullition of an ether and that 
of the acid whose radicle it contains : 





Point of ebullition. 


Difference. 


Formic acid, 


' - 105° ) 
- 55° [ 




" ether, 


50° 


Acetic acid 


- 118° ( 




" ether, 


74° j" 


U° 


Propionic acid, 


- H0° ) 
95°) 




" ether, - 


45° 


Butyric acid, 


163° ) 




" ether, - 


- 119° \ 


4A° 



The solubility in water of the ether formed by 
homologous acids varies with the molecular weight ; 
thus formic ether is quite soluble, acetic ether is less 
soluble, butyric ether is but slightly so, and valerianic 
ether, which follows it, is nearly insoluble. 

MERCAPTANS AND THEIR ETHERS. 

Od substituting sulphur, selenium, or tellurium for 
oxygen in the alcohols of different atomicity, sulphur, 
selenium, or tellurium alcohols are obtained, which 
are designated as mercaptans, selenium mercaptans, 
and tellurium mercaptans. 

Ethers proper correspond to these as to ordinary al- 
cohols. These ethers are derived either by the substi- 



ETHERS. 83 

tution of an alcohol radicle for the typical hydrogen, 
as happens with monatomic mercaptans, or by the 
elimination of H 2 S, as is the case with biatomic mer- 
captans. 

One only of each of these two classes will be alluded 
to here. 

Ethyl sulphide, or hydrosulphu- Lnn = C 2 H 5 \ g 
ric ether, j 4 10 C 2 H 5 j 

Ethyl mercaptan, C 4 H 6 S= C2 g 5 j- S. 

To prepare the sulphide a current of ethyl chloride, 
is passed into an alcoholic solution of potassium 
sulphide. 

The mercaptan is prepared by the action of potass- 
ium hydro-sulphide on ethyl sulphide. 

In either case potassium chloride is formed. 

K 2 S +2C 2 H 5 C]==C 4 H 10 S-I-2KC1 
KHS + C 2 H 5 C1=C 2 H 6 S + KC1. 

These bodies are afterwards separated by distillation. 
Like all the sulphur derivatives of alcohol, they have a 
nauseous odor. The sulphide boils at 91° the mer- 
captan at 36°. 

MIXED ETHERS 

containing two different radicles, are obtained by act- 



84 ORGANIC CHEMISTRY. 

ing, for instance, with ethyl iodide upon potassium 
me thy late, thus : 

ethyl iodide, potassium potassium methyl-ethyl 
methylate. iodide. ether. 

or by acting on hydric methyl sulphate rr 8 \ S0 4 

with ethyl alcohol. The following is a list of some of 
the more important mixed ethers of the monatomic 
series; 

TABLE OF MIXED ETHERS. BOILING POINT. 



Methyl-ethyl ether C 3 H 8 0= £j |[ 3 | O + 11° 

Methyl-amyl ether C 6 H 14 =£ § 3 1 O 92° 

Ethyl-butyl ether C 6 H u O = ^|* 5 \ O 80° 

Ethyl-amyl ether C 7 H 16 = ^ 2 ^ 5 \ O 112° 

Ethyl-hexyl ether C 8 H 18 - £?| 5 | O 132°. 



ALDEHYDS. 85 



ALDEHYDS. 

The following are the principal aldehyds, arranged 
in series: 

C n H 2n O. 



Formic aldehyd 


C H 2 


Ethylic aldehyd 


C 2 H 4 


Propylic aldehyd - 


- 3 H 6 O 


Butylic aldehyd - 


C 4 H 8 


Valeric aldehyd 


C 5 H 10 O 


OEnanthylic aldehyd - 


C? H14O 


Caprylic aldehyd - 


- C 8 H 16 


Caproic aldehyd 


C 10 H 20 O 


Eutic aldehyd 


CnH 22 


Ethalic aldehyd 


CjeH^O 


CnH 2n . 2 0. 


• 


Allylic aldehyd {acrolein) - 


C 3 H 4 


C n H 2n . 4 0. 




Campholic aldehyd {camphor) C 10 H 16 O 



86 ORGANIC CHEMISTRY. 

C n H 2n ^O. 

Benzoic aldehyd (oil of hitter almonds) C 7 H 6 O 
Toluic aldehyd - - - - C 8 H 8 
Cuminic aldehyd - C 10 H 12 O 

Sycocerylic aldehyd - - - C 18 H 28 

C n H 2n .. 10 O. 

Cinnamic aldehyd (oil of cinnamon) - C 9 H 8 0. 

Aldehyds may be regarded as bodies built upon the 
type of one or more molecules of hydrogen, in which 
one half the hydrogen atoms are replaced by one or 
more molecules of an oxidized carbohydride. 

The formation of aldehyd, ($Zcohol dehydrogensited), 
may be illustrated by the following equation: 

C 2 H 6 — H 2 = C 2 H 4 



Ethyl alcohol. Ethyl aldehyd. 

Aldehyds are obtained by the oxydation of alcohols, 
but they are only the first products of oxydation. They 
are capable of combining with an additional molecule of 
oxygen, forming acids; hence the aldehyds are inter- 
mediate between alcohols and acids. 

ORDINARY ALDEHYD. 

C 2 H 4 O=0 2 H 3 O 
'H 

This substance is formed by the slow oxydation of 
alcohol. 



ALDEHYDS. 87 

Alcohol is treated with, a mixture of manganese 
binoxide, or of potassium bichromate, and sulphuric 
acid, and distilled, care being taken to keep the re- 
ceiver well cooled. Besides aldehyd, acetyl, acetic 
ether, acetic acid and water are formed. The product 
is again distilled, care being taken to collect only that 
portion which passes over above 60°. This liquid is 
mixed with ether, and, when cool, a stream of dry 
ammonia gas is caused to pass through the solution. 
Crystals of ammonium aldehyd are formed, 
C 2 H 3 (]S T H4)0, which are decomposed by dilute sul- 
phuric acid. The mixture is then distilled. 

Aldehyd is a colorless, very volatile liquid. It is 
soluble in water, alcohol and ether, and possesses a 
strong, somewhat stifling odor. 

The salient property of aldehyd is its avidity for 
oxygen. If a few drops are poured into water the 
latter becomes acid; it is therefore a valuable reduc- 
ing agent. 

If aldehyd, or ammonium aldehyd, VrVr f is 

poured into an ammoniacal solution of silver nitrate, 
on slightly elevating the temperature, metallic silver is 
deposited. This silver adheres to the sides of the tube, 
and covers it with a mirror-like coating. This prop- 
erty is the basis of a process of silvering glass globes 
and other hollow articles of glass. 

Aldehyd is attacked by chlorine and bromine, and 
furnishes, by substitution, various products, of which 

Chloral C 2 HC1 3 0, is the most important. Ily. 



SO ORGANIC CHEMISTRY. 

drate of chloral, or C 2 HC1 3 + H 2 0, liasbeen prepared 
now for several years in very large quantities, for 
medicinal purposes. Its name is derived from chlor- 
ine alcohol. 

Absolute alcohol is saturated, first cold, then hot, 
with dry chlorine. The liquid obtained is mixed with 
its volume of concentrated sulphuric acid. The 
supernatant liquid is decanted, and distilled in an 
earthern retort, with one-fourth its weight of sulphuric 
acid. The anhydrous chloral obtained is re-distilled 
twice with calcium carbonate and 7 to 8 per cent, of 
water. The hydrate is then obtained in handsome 
crystals, C 2 HC1 3 + H 2 0, soluble in water. It has 
been known for some time that this body is decom- 
posed in presence of alkalies or alkaline carbonates, 
into chloroform and formic acid, 

CJBCLO + HoO + KHO = KCHO, + CHC1, + H 2 0. 



Potassium Chloroform, 
formiate. 



The question appeared pertinent whether a similar 
transformation' would be effected in the human body, 
under the action of the alkaline fluids there present, 
notably those of the blood, and thus develop chloro- 
form. 

Liebreich was the first to administer chloral, and he 
at once obtained the anesthetic effects of chloroform. 
His experiments were repeated in different countries, 
and hydrate of chloral soon came into general use as 
a hyponotic. 



ALDEHYDS. 89 

Chloral hydrate for medical use must be crystalline 
and possess the following properties: it should be col- 
orless, transparent, and have an aromatic odor, a caus- 
tic taste, readily soluble in water without furnishing 
drops of oil, also soluble in alcohol, ether, naphtha, 
benzol, and carbon bisulphide; it should fuse at 56° to 
58°, solidify at about 15°, boil and volatilize completely 
at 95°. With caustic potassa it should furnish chloro- 
form, and with sulphuric acid, chloral, without becom- 
ing brown. Its aqueous solution should be neutral 
and not produce any turbidity with silver nitrate and 
nitric acid. Exposed to the air it should not become 
moist. According to recent investigations by Liebreieh, 
(60-69-673) chloral produces the opposite physiolog- 
ical effects of strychnine, hence, these bodies may 
be used as antidotes one for the other. 

The remaining aldehyds are not sufficiently im- 
portant for a work of this scope. Camphor has al- 
ready been considered in connection with turpentine. 



90 OEGANIO CHEMISTRY. 



OKGANTC ACIDS. 

ACIDS CONTAINING TWO ATOMS OF OXYGEN. 
FATTY ACID SERIES. 
C n H 2n 2 . 



Formic 


acid, - 


C H 2 2 


Acetic 


u 


C 2 H 4 2 


Propionic 


a 


C 3 H 6 2 


Butyric 


a 


4 H 8 O, 


Yaleric 


a 


C 5 H, O 2 


Caproic 


u 


- C 6 Hi,0 2 


(Enantlrylic 


u 


C 7 H 14 0. 2 


Caprylic 


a _ 


C 8 H 16 2 


Pelargonic 


a 


C 9 Hi 8 2 


Capric 


a 


CioH 20 2 


Laurie 


a 


O u H,A 


Coccinic 


a 


Ci 3 H 26 2 


My ri stic 


« - 


Ci4H 28 2 


Palmitic 


" 


Ci 6 H 32 2 


Margaric 


a 


C 1T H 34 2 


Stearic 


a 


^18-^-36^2 


Arachidic 


" 


" ^20^40^2 


Cerotic 


" 


O^H^Oa 


Melissic 


" . 


CsqILqqO^ 



ORGANIC ACIDS. 93 



C n H2n-2^2- 




Acrylic acid - 


O3H4O2 


Crotonic " 


C 4 H.O a 


Angelic " - 


C 5 H 8 2 


Pyroterebic " 


C 6 H 10 O 2 


Campholic " - 


CioH 18 2 


Moringic " 


• C 15 H 28 2 


Physetoleic " - 


Ci 6 H 30 O 2 


Oleic " 


Ci 8 H 34 2 


Doeglic '' 


^1Q^-B&^2 


Erucic " 


C 22 H420 2 . 


C n H 2n _40 2 . 




Sorbic acid 


C 6 H 8 2 


Camphic " 


C 10 H 16 O 2 - 


AROMATIC ACID SERIES. 


CiAn-sOa. 




Benzoic acid 


C 7 H 6 2 


Toluic " 


C 8 H 8 2 


Xylic " 


C 9 H 10 O 2 


Cumic " 


C 10 H 12 O 2 


Alpha-cymic acid 


CnH 14 2 « 


C n II 2n _ 10 O 2 . 




Cinnamic acid - - . 


C 9 H 8 2 


Pinic " - . - 


C^HsqO^ 



92 ORGANIC CHEMISTRY. 

ACIDS CONTAINING THREE ATOMS OF OXYGEN. 
C n H 2n 3 . 



Carbonic acid 


C H 2 3 


Glycolic " - 


C 2 H 4 3 


Lactic " - 


C 3 H 6 0, 


Oxybutyric " 


C 4 H 8 3 


Oxy valeric " 


C 5 H 10 O 3 


Leucic " - 


C 6 H 12 3 


CEnanthic " 


C^H^Os. 


C n H 2n _20 3 . 


• 


Pyruvic acid 


C 3 H 4 3 


Scammonic " 


C 15 H 28 3 


Ricinoleic " - 


C 18 H340 3 . 


^n-U-2n— 4^3* 




Ouaiacic acid 


6 H 8 0, 


Lichenstearic " - - 


C 9 H 14 3 . 


CnH 2n _60 3 . 




Pyromeconic acid 


C 5 H 4 O s . 


CnH 2n _80 3 . 




Salicylic acid - 


C 7 H 6 3 


Anisic " 


C 8 H,0 3 


Pliloretic " - 


C 9 H :0 O, 


Oxycuminic " 


C I0 H 12 O 3 


Thymotic " - - 


C n H 14 3 . 



OBGANTC ACIDS. 93 

Coumaric acid - - C 9 H 8 3 . 

ACIDS CONTAINING FOUR ATOMS OF OXYGEN. 

C n H 2n 4 . 
Glyceric acid C 3 H 6 4 . 

C n H 2n _ 2 4 , 



Oxalic 


acid 


0,H,O 4 


Malonic 


u 


C 3 H 4 4 


Succinic 


a 


4 H 6 4 


Pyrotartaric 


a 


5 H 8 O 4 


Adipic 


a 


6 H 10 O 4 


Pimelic 


a 


C? H 12 4 


Suberic 


a 


C 8 H 14 4 


Anchoic 


a 


C 9 H 16 4 


Sebic 


a 


Ci H 18 O 4 


Eoccellic 


u 
CnH 2n _ 4 4 . 


C 17 H 32 4 . 


Fumaric 


acid 


C 4 H 4 4 


Citraconic 


u 


C 5 H 6 4 


Terebic 


u 


O,H 10 O 4 


Camphoric 


u 


Ci H 16 O 4 


Lithofellic 


a 


^20^-26^^ 



94 



OEGANIC CHEMISTET. 




CnH2 n _60 4 . 




Mellitic 
Terechrysic 


acid 
u 

C n H 2n _804. 


CflO, 
C 6 H 6 4 . 


Yeratric acid 


C n H 2n _io04. 


C 9 H 10 O 4 . 


Phtalic 

Insolinic 

Choloidic 


acid 

u 
G n H2n-14^'4- 


C 8 H 6 4 
C 9 H 8 4 


Oxynaphthalic acid 
Piperic " 


Ci H 6 4 

C 12 H 10 O 4 . 



ACIDS CONTAINING 5, 6, 7 AND 8 ATOMS OF OXYGEN. 

C n H 2n _20 5 . 

Tartronic acid C 3 H 4 5 

Malic " C 4 H 6 5 . 

C n H 2n _40 5 . 

Mesoxalic acid C 3 H 2 O g . 

CnH^^Os. 



ORGANIC ACIDS. 




Cholesteric acid 


C 8 Hi Og. 




CnH 2n _ 8 5 . 




Croconic 


acid 


C 5 H 2 5 


Comenic 


u 


C 6 H 4 5 


Gallic 


u 


7 H 6 O 5 


Cholalic 


C n H 2n _ 2 6 . 


C^H^C^. 


Tartaric acid 




4 H 6 O 6 


Quinic " 


C n H2n-40 6 . 


C 7 H 12 6 . 


Carballylic acid 


C 6 H 8 6 . 




C n H 2n _60 6 . 




Aconitic acid 


C n H 2n _ 10 O 6 . 


C 6 H 6 6 . 


Chelidonic 


acid 

C n H 2n _ 10 O 7 . 


0,H 4 O 6 


Meconic 


acid 


C7II4 Of 


Citric 


acid 


C 6 H 8 7 


Mueic 


u 


C 6 H 10 O 8 . 



95 



Org anic acids are bodies built upon the type of one 
or more molecules of water , having one half the hy- 
drogen replaced by an organic compound radicle con- 



96 ORGANIC CHEMISTRY. 

taining oxygen. There are some acids whose compo- 
sition is not definitely fixed. We shall first examine 
the monatomic acids, and study the other series in the 
order of their atomicity. 

The organic acids possess the general properties of 
the mineral acids. Many among them, like acetic acid, 
have a very decided action upon litmus. Generally, 
they are solid and crystallizable; however, formic, pro- 
pionic, butyric acids, etc., are liquid. Acids whose 
molecules are comparatively simple, are ordinarily sol- 
uble in water — the others are little, or not at all, soluble 
in this solvent. The monobasic acids are volatile, at 
least where their molecules are not very complex. The 
polybasic acids are decomposed by heat. Their salts 
are ordinarily crystallizable. 

METHODS OF PREPARATION. ' 

I. The acids of the so-called fatty series are ob- 
tained by the oxidation of the corresponding alcohol, 
or aldehyd, which latter is the first product of oxida- 
tion of the respective alcohol. 

C 2 H 6 + O =C 2 H 4 + H 2 0. 



Y 

Acetic aldehyd. 



C 2 H 4 + 0=C 2 H 4 0, 



Acetic acid. 



II. These acids are also produced by the action of 
alkalies upon the cyanide of the radicle appertaining 
to the homologous inferior alcohol. 



ORGANIC ACIDS. 97 

(CH 3 )(m + KHO + H 2 0=NH 3 + KC 2 H 3 2 . 



Methyl cyanide. Potassium acetate. 

III. Acids are likewise formed by the union of the 
elements of carbon monoxide and carbon dioxide with 
hydrogen carbides and water. The remarkable syn- 
thesis of formic acid by Berthelot is, according to this 
method : 

CO + H 2 0=CH 2 2 . 

Pelouze has shown that heat, carefully applied to 
polyatomic acids, causes them to part with a certain 
number of molecules of water, of carbon dioxide, or of 
both, and furnishes acids more simple and of a lower 
equivalence, which he designates by the name oipyro- 
acids. 

2C 4 H 6 6 =C 5 H 8 4 + 2H 2 + 3C0 2 . 



v 

Tartaric acid. Pyro-tartaric acid. 



Of all the series of acids, the most numerous and the 
most important are those of the so-called fatty series- 
We shall presently indicate the methods by which they 
are obtained. 

Their boiling point increases from 15° to 20° with 
each addition of Cli 2 to their molecule. Certain of 
their salts, those of calcium, for instance, are decom- 
posed by heat, furnishing compounds called acetones. 



98 ORGANIC CHEMISTRY. 

Ca(C 2 H 3 2 ) 2 =CaC0 3 + C 3 H 6 0. 



Calcium acetate. Ordinary acetone. 

FORMIC ACID. 

CH,0 2 =CH O ) Q 

Red ants made to pass over moistened blue litmus 
paper produce red stains. The acid secreted by 
these insects was first obtained bj Gehlen, and has re- 
ceived the name of formic acid. 

I. Berthelot has obtained it from carbon mon- 
oxide by synthesis. 

II. It is prepared by distilling a mixture of 10 
parts of starch, 30 parts of sulphuric acid, 20 parts of 
water, and 37 parts of manganese binoxide in a large 
retort connected with a condenser. 

The mass swells considerably, and at first must be 
heated but gently. The formic acid is distilled over 
and saturated with lead carbonate. The fbrmiate of 
lead is caused to crystallize in boiling water, then 
placed in a retort and decomposed by a current of hy- 
drogen sulphide and thereupon heated; the formic acid 
is then distilled off. 

III. One kilo of glycerine, 150 to 200 grams of water 
and 1 kilo, of oxalic acid are introduced into a retort 
and heated for 15 hours at a temperature of about 100°. 
The oxalic acid is decomposed, but only carbon di- 
oxide is disengaged. "Water is added from time to 



ACETIC ACID. 99 

time, and the mixture then distilled until 8 litres have 
passed over. The glycerine remains unchanged in the 
retort, and can again be used. 

Formic acid is a colorless liquid, of a very acid re- 
action, a pungent odor and crystallizing at about 0° 
and boiling at 10i°. 

It reduces oxide of mercury, furnishing mercury, as 
a brown powder, also carbon dioxide and water. Its 
salts are usually soluble, though that of lead is very 
little soluble in cold water, but quite soluble in boil- 
ing water. 

On heating with sulphuric acid, carbon monoxide 
and water are formed. 

Experiment. — Introduce into a test-tube a small 
quantity of formic acid or a formiate. Add sulphuric 
acid and heat; a regular liberation of a gas takes place, 
which may be ignited, producing a blue flame. 

CH 2 2 = CO-f-H 2 0. 



ACETIC ACID. 

C 2 H 4 2 =C 2 H 3 0) a 

Sp. Gr. 1.08. Density, of vapor 30. 

Glacial acetic acid melts at 17° ; boils at 118°. 

This is the acid of vinegar, and of which it forms 
the essential part. It is found in the juices of many 
plants and in certain fluids of the body. It is formed 
by synthesis from methyl, sodium, or potassium for- 



100 ORGANIC CHEMISTRY. 

miate, and by the oxidation of acetylene; also by the 
action of nitric acid upon fatty substances, and by the 
reaction of potassa upon tartaric, malic and citric acids. 
It is further produced : 

I. By the oxidation of alcohol in the following way: 
Wine in vats, or casks, is placed in a cellar main- 
tained at a temperature of about 30°; every sixth or 
eighth day several litres of vinegar are withdrawn and 
replaced by an equal quantity of wine. 

Pasteur has established that the oxydation of alco- 
hol is produced by a minute plant, the Mycoderma 
aceti. In fact, acetification commences only when 
this plant has been formed in the liquid. If 
its development is interrupted the oxydation stops; it 
renders the service of taking oxygen from the air and 
transferring it to the alcohol. 

This process is very slow. It may be rendered more 
rapid by pouring dilute alcohol on beach-wood shav- 
ings placed in barrels. The air penetrates through 
openings made in the lower portion. The alcohol, 
after having been passed over the shavings four times, 
will be found sufficiently acetified, if the temperature is 
maintained at about 25°. 

II. Distillation of wood. Pyeoligneotts acid. 
Wood is distilled in retorts , yielding vapors and gases. 
The former are condensed by causing them to pass 
through a condenser ; the gases are conducted under 
the retorts, where they are burned, and the heat util- 
ized in the distillation of the wood. 

The condensed liquids are water, acetic acid, wood 



ACETIC ACID. 101 

spirit and tar ; the greater portion of the tar is me- 
chanically removed and the remaining liquid distilled 
in a water bath. The wood spirit, which boils at 63° 
passes into the receiver. The water and acetic acid- 
remaining in the retort are saturated with sodium 
carbonate, the product is evaporated to dryness and 
heated from 250° to 350° ; this temperature, while not 
effecting the decomposition of the sodium acetate 
is sufficient to carbonize the tarry substance remaining 
in solution. The mass is thereupon dissolved in water, 
filtered, and the acetate allowed to crystallize. If it is 
desired to obtain the acetic acid uncombined, the solu- 
tion of the salt is distilled with a slight excess of sul- 
phuric acid. 

The acetic acid which distils over contains 'a large 
amount of water. JSTormal, or anhydrous acid may be 
obtained from it by saturating half of the liquid with 
sodium carbonate, then adding the remainder to this 
solution; acid sodium acetate is thereby produced, 
which is evaporated to dryness and distilled with sul- 
phuric acid. This liquid, cooled with ice, gives crystals 
of normal acetic acid, which can be separated on de- 
canting the liquid, furnishing the so-called glacial 
acetic acid. 

Acetic acid is liquid above 17°; below that it crys- 
tallizes in handsome plates. It is a strong acid, has a 
pronounced odor, and is very caustic, producing blis- 
ters on the skin. It is soluble in water, alcohol and 
ether in all proportions. It dissolves resin and cam- 
phor, also fibrin and coagulated albumen. On uniting 



102 ORGANIC CHEMISTRY. 

with, water it contracts in volume. A red heat de- 
stroys it, many products being formed; methane, 
acetylene, acetone, benzol, naphthalin, etc. , also car- 
bon, which remains in the retort. 

If a flask containing chlorine gas and a small quan- 
tity of acetic acid, is exposed to the sunlight, trichlor- 
acetic acid is formed, 2 Vr [• O. This experi- 
ment of Dumas served as a basis for the theory of 
substitution. Le Blanc has also obtained monochlor- 
acetic acid C 2 H 2 C10 j Q Thege chlorine products are 

reduced to the state of acetic acid by reducing agents, 
such as sodium amalgam in presence of water, 

(H 2 ) 3 +C 2 HCl 3 2 =3HCl+CoH 4 2 . 

In the same manner as acetic acid, heated with an 
excess of a base, furnishes marsh gas, trichlor, 
acetic acid produces trichlorinated marsh gas, which 
is chloroform, 

2 HA+BaO=BaCO 8 + CH 4 

C 2 HCl 3 2 +BaO=BaC0 3 + CHC1 3 . 

Perchloride of phosphorus, in the hands of Gerhardt, 
has become the means of an important discovery, that 
of acetic anhydride and in general of the anhydrides 
of the monobasic acids. If dry sodium acetate (3 
parts) is mixed with the perchloride, or better, with oxy- 



VINEGAK. 



103 



chloride of phosphorus, (1 part), and then distilled, a 
chloride is obtained called acetyl chloride, 

C 2 H 3 0C1=C 2 H 3 

CI 

acetyl being the radicle of acetic acid. This chloride, 
subjected to the action of an excess of sodium acetate, 
is decomposed and furnishes acetic anhydride, 



C 2 H s O 
C 2 H 3 



O, 



(also called acetate of acetyl) or acetic oxide, which 
boils at 139°. Water destroys it, acetic acid being 
produced. Chloride of acetyl is an irritating liquid, 
boiling at about 158°, decomposable by water into 
acetic and hydrochloric acids. 

A derivative of acetic acid of considerable theoretical 
importance is cyanacetic acid C 3 H 3 N02=C 2 H 3 j n 

CN[ U ' 
a crystalline body forming salts with the metals, which 
have been studied by T. Menies. On acting with sul- 
phuric acid and zinc on cyanacetic acid, the author 
[82-67-69] obtained formic and acetic acids and am- 
monia. 

Yinegar. This name is given to the mixture which 
is obtained by the acetification of wine, whiskey, infu- 
sion of malt, etc. Good acetic vinegar is of an agree- 
able taste and aroma. Wood vinegar has a very 
strong disagreeable taste and odor. It is frequently 



104 



OEGANIC CHEMISTEY. 



adulterated with sulphuric acid. An addition of -j^tf 
of its weight of this acid is, however, not considered 
fraudulent, as its presence is regarded necessary to 
prevent moulding. 

A ready method of detecting mineral acids, pro- 
posed by M. Witz (77-75-268), is based upon the use 
of methyl-aniline, which undergoes no change in con- 
tact with acetic acid, but promptly changes to a green- 
ish-blue in presence of the least trace of mineral acid. 

"Vinegar and concentrated acetic acid are employed 
in medicine as stimulants. 

An acetate, or acetic acid, can be recognized by heat- 
ing it slightly with sulphuric acid and alcohol ; a 
fragrant odor, characteristic of acetic ether, is observed. 
Heated with sulphuric acid alone, the acetates liberate a 
vapor which has the odor of vinegar. 

The following reaction permits of the detection of 
mere traces of acetic acid; it is saturated with potas- 
sium carbonate and heated with arsenous oxide in a 
test tube; fumes and a nauseating odor are given off. 

The author finds that one of the simplest tests for 
acetic acid, is to direct a fine, yet powerful stream of 
water into a test-tube, containing a few drops of the 
liquid to be tested. The very fine, white efferves- 
cence resulting is entirely characteristic of this acid, 
none of the other ordinary acids producing the same 
effect. 

Alcohol should not be present, as it causes a similar 
effervesence. If the acetic acid is combined it should 
be set free with a strong mineral acid. By this test, 



ACETATES. 105 

perhaps more physical than chemical, acetic acid, di- 
luted with 1000 parts of water, can be readily recog- 
nized, and with practice, one part in 1500. 

ACETATES. 

Acetic acid is monobasic; there are, however, alka- 
line biacetates and some basic acetates of copper and 
lead. 

POTASSIUM ACETATE. 

KC 2 H 3 2 = C 2 H 3 0) 

This salt, distilled with its weight of arsenous oxide, 
furnishes a very inflammable liquid, formerly called the 
"liquor of Cadet," and in which Bunsen has found a 
radicle spontaneously inflammable, cacodyl, C 4 IT 12 As 2 . 

Potassium acetate forms, as well as sodium acetate, 
an acid acetate when treated with acetic acid. It is a 
very deliquescent salt, difficultly crystallizable. 

AMMONIUM ACETATE, 

NH 4 C 2 H 8 2 , 

Is prepared by saturating ammonium carbon- 
ate with acetic acid. Its solution constitutes the 
spirit of Mindererus ; treated with phosphoric oxide it 
forms cyanide of methyl. There is also an acid salt, 
NH 4 C 2 H 3 2 C 2 H 4 2< In compounds of this character, 



106 ORGANIC CHEMISTRY. 

acetic acid must be considered as acting the same part 
as the water of crystallization in salts. 

SODIUM ACETATE. 

]STaC 2 HA+3H 2 0. 

This is used in preparing marsh gas and concentrated 
acetic acid. It is recommended by Tommase (52-72- 
23), as a solvent for plumbic iodide, of which two grams 
are readily dissolved in 0.5 c. c. of a strong solution of 
sodium acetate. 

CALCIUM ACETATE. 

Ca(C 2 H 3 2 ) 2 . 

This salt, subjected to distillation, furnishes a liquid 
containing a large proportion of acetone C 3 H 6 0- 

ALUMINUM ACETATE. 

A1(C 2 H 3 2 ) 3 . 

This body is employed at present by dyers, as a mor- 
dant. It is prepared by causing aluminum sulphate 
to react upon lead acetate. Lead sulphate, which is 
insoluble, is separated on filtering the liquid. 

FEEKIC ACETATE. 

This salt {pyrolignite) has been, and is still, 
somewhat employed for the preservation of wood. 



ACETATES. 107 

COPPER ACETATES. 

Normal acetate Cn(C 2 H 3 2 )o is called verditer. It 
forms beautiful green crystals (crystals of Venus), 
which, subjected to distillation, furnish acetic 
acid mixed with acetone. During this operation, a 
white sublimate is formed, which deposits in the neck 
of the retort. This latter is cuprous acetate, and is car- 
ried over into the receiver, oxydizes, and changes into 
cupric acetate, which colors the distillate blue. There 
remains in the retort, after this decomposition, very 
finely divided copper which takes lire when slightly 
heated in the air. Solutions of this acetate reduce the 
salts of the oxide, CuO, and serve to prepare the sub- 
oxide, Cu 2 0. 

A basic acetate, designated by the name of verdigris, 
is obtained by exposing to the air sheets of copper 
moistened with vinegar, or surrounded by the marc of 
grapes. The metal becomes covered with a greenish 
incrustation whose formula is, 

Cu(C 2 H 3 2 ) 2 ,CuO+6H 2 0. 

LEAD ACETATE. 

The normal acetate Pb(C 2 H 3 2 ) 2 is prepared by treat- 
ing litharge with acetic acid in slight excess. This salt, 
known by the name of sugar of lead, crystallizes in 
oblique rhombic prisms, soluble in two parts of water 
and eight parts of 95 per cent, alcohol. It has a sweet 
taste, and is very poisonous. It is employed as a re- 



108 ORGANIC CHEMISTRY. 

agent, also to prepare aluminum acetate and lead chro- 
mate. 

In digesting acetic acid with an excess of litharge, it 
furnishes a hexabasic acetate of lead. If ten parts of 
normal acetate, with seven parts of litharge are taken and 
this mixture digested with 30 parts of water, there are 
formed minute needles of a tribasic salt Pb(C 2 H 3 2 ) 2 , 
Pb02, H 2 0. Finally this salt, dissolved in normal ace- 
tate, gives a sesquibasic acetate, which is deposited in 
crystals, 2(Pb2C 2 H 3 2 ),PbO,H 2 0. 

Goulard's exteact is a solution containing a mix- 
ture of normal and of sesquibasic acetate of lead, 
which is prepared by boiling 30 parts of water, 7 parts 
of litharge and 6 j^arts of normal acetate of lead. 

BUTYRIC ACID. 



C 4 H 8 2 = C4H £i0. 



H 

It is usually prepared as follows: a mixture of 
10 parts of sugar, 1 part of white cheese, 10 parts of chalk, 
and some water, is maintained at a temperature of 30° 
to 35°. First, lactate of lime is formed, which causes 
the mass to thicken, then that salt changes into buty- 
rate, disengaging hydrogen and carbon dioxide. "When 
the mixture has become clear, the liquor is evaporated 
and the butyrate separated with a skimmer. This 
salt is decomposed by concentrated hydrochloric acid 
which separates the butyric acid in the form of an oil, 
which is distilled off. It boils at 163°. It is of a 
fetid odor, and soluble in water, alcohol and ether. 



VALERIC ACID. 109 

Valerianic, ok Valeeic Acid C 5 H 10 O 2 = 5 tt f O- 

It can be obtained by oxydizing amylic alcohol by 
a mixture of potassium bichromate and sulphuric acid v 
or by distilling valerian root with water acidulated 
with sulphuric acid. The best method is to boil por- 
poise oil with water and lime. The oil saponifies and the 
valerianate of calcium alone is dissolved. This liquid 
is concentrated and hydrochloric acid added in excess. 
The valerianic acid separates out in the form of an oil 
which is distilled, and that portion collected which 
passes over at 175°. 

Pierre and Puchot have lately devised a process for 
preparing valeric acid from amyl alcohol. (3-[3] 5-40. ) 

BENZOIC ACID, C 7 H 6 2 . 

Density, 61. 

Density of its vapor compared with air, 4.27. 

Melts at 120°; boils at 250°. 

It is obtained by a dry, as also by a wet process. 
To prepare it by the former method, equal weights of 
sand and gum benzoin are placed in an earthen ves- 
sel, the mixture covered with a sheet of filter paper, 
which is pasted down round the edge, and a long cone 
of white cardboard placed over the whole. The 
earthen vessel is then heated over a slow fire for two 
hours, and when cool the cone is removed. The ben- 
zoic acid is found to have condensed on the interior 
of the cone in handsome blades, or needles. 



110 ORGANIC CHEMISTRY. 

It is obtained, in the wet way, by pulverizing gum 
benzoin, mixing it with half its weight of lime, and 
boiling for half an hour in a cast-iron kettle, with six 
times its weight of water, care being taken to agitate 
the mixture. It is thrown upon a piece of linen and 
the residue treated twice with water. The liquids are 
reduced in volume to two-thirds that of the water used 
during the first treatment, then saturated with hydro- 
chloric acid. The benzoic acid separates out, and is 
recrystallized from a solution in boiling water. 

It is also procured from the urine of herbivorous 
animals. This secretion, evaporated to a small bulk 
and treated with hydrochloric acid, yields a deposit of 
hippuric acid, which, on being heated with dilute sul- 
phuric acid, is transformed into benzoic acid. 

Benzoic acid is also produced on a large scale from 
naphthalin. 

Benzoic acid crystallizes in lustrous blades, or need- 
les, is little soluble in cold water, quite soluble in boiling 
water, and still more so in alcohol and ether. On 
passing its vapors through a tube heated to redness, it 
is decomposed into benzol and carbon dioxide, 
C 7 H 6 2 = C 6 H 6 +C0 2 . Chlorine, bromine and nitric 
acid transform it into substitution products. 

Chlorbenzoic acid, C 7 H 5 C10. 
Dinitrobenzoic " C 7 E 4 (N0 2 ) 2 2 . 

Ammonium benzoate furnishes, on distillation, ben- 
zonitrile C 7 NH 9 2 = C 7 H 5 N" + 2H 2 0. 

The alkaline benzoates heated with chloride, or 



BENZOIC ACID. Ill 

oxychloride of phosphorus, furnish benzyl chloride, 
which, submitted to the action of potassium benzoate 
in excess, gives benzoic anhydride, 

3(KC 7 H 5 2 )+P0C1 3 - 3(C 7 H 5 0C1)+K 3 P0 4 . 

v j 

Y 

Chloride of benzyl. 

0^3*001 + KC 7 H 5 2 = C 14 H 10 O 3 + KCl. 

Benzoic anhydride. 

The rational formula of benzoic anhydride is, 

c,n 5 o) 

C 7 H 5 \ u - 

Calcium benzoate heated to a high temperature 
furnishes benzone, 

Ca(C 7 H 5 2 ) 2 = CaC0 3 +CO(C 6 H 5 ) 2 . 



Calciumbenzoate. Benzone. 

Benzoic acid is monobasic, and the benzoates are 
generally soluble. Benzoic acid taken into the stom- 
ach, is transformed into hippuric acid. 

Kolbe and von Meyer have observed that benzoic 
acid has antiseptic power, though less than salicylic 
acid, (18-[2]12-133). 

cinnamio acid. In certain balsams there exists an 
acid called cinnamic acid, whose formula is C 9 H 8 2 . 
It exists in the balsams of Peru, benzoin, tolu and in 
liquid storax. It fuses at 129° and boils at 290°. It 



112 ORGANIC CHEMISTRY. 

has striking features of resemblance to benzoic acid, 
and is produced like the latter bj the oxjdation of an 
aldehyd. This aldehyd is the essence of cinnamon 
prepared by distilling cinnamon with water. 

POLYATOMIC ACIDS. * 

OXALIC ACID. 

Preparation. In the burdock and sorrel is found 
an acid salt, commonly called salt of sorrel, which is 
a mixture of binoxalate and quadroxalate of potas- 
sium. Sodium oxalate is found in several marine 
plants, calcium oxalate in the roots of the gentian 
and rhubarb, and in certain lichens. Salt of sorrel is 
extracted from the burdock {Prunex\ in Switzerland, 
and in the Black Forest of Germany, by expressing 
the plant, clarifying the expressed liquid by 
boiling with clay, and evaporating ; crystals of salt of 
sorrel are deposited. 

The oxalic acid may be obtained free by decompos- 
ing a solution of these crystals with lead acetate ; 
the oxalate of lead which precipitates is treated with a 
suitable quantity of sulphuric acid ; the lead is com- 
pletely precipitated as lead sulphate ; this is filtered 
off, and the liquid evaporated and allowed to crys- 
tallize. 

At present this acid is chiefly prepared by the action 
of oxydizing agents upon certain organic substances^ 
the substances best suited for this purpose are those 



OXALIC ACID. 113 

which contain oxygen and hydrogen in the proportion 
to form water. One part of starch, or sugar, is boiled 
with eight parts of nitric acid diluted with ten 
parts of water, until nitrous vapors cease to be disen- 
gaged, and the liquid then evaporated. The crys- 
tals of oxalic acid which separate out are freed from 
the excess of nitric acid, by being several times re- 
crystallized in water. It is also obtained on a large 
scale by the action, at a high temperature, of potass- 
ium or sodium hydrate on saw dust. 

Oxalic acid has been obtained synthetically, by 
Drechel,on passing carbon dioxide over sodium heated 
to 320°. 

2C0 2 +Na 2 =ISra 2 C 2 4 . 

Properties. — Oxalic acid crystallizes in prisms, 
which effloresce in the air, and which are very soluble 
in water and alcohol. 

It fumes at 9S°; at 170° to 180° it is partially sub- 
limed, but the greater portion is decomposed into car- 
bon monoxide, carbon dioxide, formic acid and water. 

2(C 2 H 2 4 )=CO +2C0 2 +CH 2 2 +H 2 0. 

Chlorine, hypochlorous acid, fuming nitric acid and 
hydrogen peroxide, convert oxalic acid into carbon 
dioxide. 

Sulphuric acid causes it to split up into carbon mon- 



114 ORGANIC CHEMISTRY. 

oxide and carbon dioxide, and this reaction is made use 
of in preparing the former gas. 

Oxalic acid is bibasic. 

Normal potassium oxalate, K 2 =0 2 =C 2 2 . 
Acid potassium oxalate, KH=0 2 = : C202. 

Uses. — Oxalic acid is employed in removing ink 
spots from cloth, and in cleaning copper. It owes these 
properties to the fact that it forms with iron and copper 
soluble salts, hence it is also employed in calico-works 
for removing colors. 

Toxic action of oxalic acid. On account of the use 
of oxalic acid in the arts, and its physical resemblance 
to certain salts, particularly to magnesium sulphate, 
poisoning with it has often occurred, either through 
design or imprudence. 

It acts powerfully upon the system. Tardieu. men- 
tions the case of a young man, sixteen years of age, 
who was poisoned by two grams of this substance. 

The symptoms observed are similar to those pro- 
duced by other corrosive agents; great prostration fol- 
lowed by unconsciousness and a persistent numbness 
in the lower extremities. The blood of the patient be- 
comes abnormally red. 

In cases of poisoning, the acid should be removed 
from the stomach with promptness, and milk of lime, 
or magnesium, or ferric hydrate administered. Lime 
is to be preferred, as it forms a salt completely insol- 
uble in vegetable acids. 



SUCCINIC ACID. 115 



SUCCINIC ACID. 



C 4 H 6 4 = C 4 H 4 2 ) o 

This acid is produced by the oxydation of butyric 
acid, and by subjecting amber, suceinum, to dry distil- 
lation or by the action of iodhydric acid on malic or 
tartaric acids. 

Succinic acid crystallizes in rhomboidal prisms which 
melt at 180° and boil at about 235°, at a higher tem- 
perature they are decomposed into water and succinic 
anhydride C 4 H 4 3 . It is soluble in 5 times its weight 
of cold water, soluble in ether and very soluble in alco- 
hol. 

It is used in the artificial preparation of malic and 
tartaric acids. Succinic acid has been found in the 
fluid of the hydrocele and of certain hydatids. 

MALIC ACID. 

C 4 H 3 2 ) n 

This acid, discovered by Scheele in sour apples, is 
found in many plants ; in the berries of the service- 
tree, in cherries, raspberries, gooseberries, rhubarb, to- 
bacco, etc. Malic acid is levogjrrate, deliquescent 
and crystallizable; it is soluble in alcohol and fuses at 
about 100°. 

At a temperature above 130°, it is decomposed into 



116 ORGANIC CHEMISTRY. 

various acids and especially paramalic acid, C 4 II 4 4 , 
which is identical with the acid of the fumaria. It 
is bibasic like oxalic acid, but triatomic and is dis- 
tinguished from this acid by not producing a turbid- 
ity with calcium compounds. 

TARTARIC ACID. 

This acid, obtained from wine tartar by Scheele, in 
1770, occurs free and combined with potassium in 
many vegetable products ; in the sorrel, berries of the 
service-tree and tamarind, in the gherkin, potato, 
Jerusalem artichoke, etc. The grape is the chief 
original source of this acid. 

One method of preparing tartaric acid is to purify 
crude tartar by dissolving and clarifying with clay, 
which throws down the coloring matters: then filter- 
ing and adding calcium carbonate, which precipitates 
half of the tartaric acid as a calcium salt. 

2KHC 4 H 4 O 6 +CaCO3=CaC 4 H 4 O 6 +KAH 4 O 6 +CO 2 +H 2 



Hydro-potassic Calcium Calcium tartrate. Potassium 
tartrate. carbonate. tartrate. 



The solution which contains the potassium tartrate, 
is filtered and calcium chloride added : the remainder 
of the tartaric acid is thus precipitated as a tartrate 
and added to the preceding. 



TARTARIC ACID. 117 

K 2 C 4 HA + CaCl 2 = CaC 4 H 4 6 + 2 KOI. 



Potassium tartrate Calcium tartrate. 

These precipitates are washed and decomposed with 
sulphuric acid, the calcium sulphate is filtered off, and 
the liquid evaporated to the point of crystallization. 
This acid is also called right tartaric, or dextroracemic, 
as it turns the plane of polarization to the right. 

Kistner has obtained from certain tartrates a tartaric 
acid which is optically inactive. This acid, called^wm- 
tartaric or racemic acid, is somewhat less soluble than 
dextrotartaric acid, while the reverse is the case with 
its salts. It contains, moreover, one molecule of water 
of crystallization, but does not crystallize, as does the 
dextrogyrate acid, in hemihedral crystals. 

Levogyrate tartaric acid is prepared by evaporating 
a solution of racemate of cinchonia; the levogyrate 
tartrate precipitates while the dextrogyrate remains in 
solution; or a solution of racemic acid is allowed to 
stand with a small quantity of calcium phosphate, and 
a few spores of the .Pencilium glaucwn; fermenta- 
tion sets in, which destroys the dextroracemic acid. 

Dextrotartaric acid crystallizes in beautiful oblique 
prisms with a rhombic base. Cold water dissolves 
twice its weight of this acid; alcohol dissolves it with 
equal facility. It is insoluble in ether. 

Tartaric acid melts at about 180°; and furnishes dif- 
ferent pyrogenous acids, chiefly: 

Tartaric anhydride, or Tartrelio acid, C 4 H 4 5 , and 

Pyrotartario acid, C 5 H 8 4 . 



118 ORGANIC CHEMISTRY. 

Simpson synthesized pyrotartaric acid and Lebedeff 
has recently (60-75-100) shown that this acid is iden- 
tical with that obtained by heating tartaric acid. 

Tartaric acid does not precipitate calcium, salts. It 
produces a turbidity with lime water, but an excess of 
acid dissolves it; by these reactions it may be distin- 
guished from malic and oxalic acids. 

Tartrates. Tartaric acid is bibasic. The two 
tartrates of potassium are : 

formal potassium tartrate, IC^H^Oe 
Hydro " " KC 4 H 5 6 . 

This latter salt is obtained by purifying the tartar 
of wine casks, and is called cream of tartar. It is used 
in the preparation of black flux, white flux, potassium 
carbonate, and tartaric acid, also largely in baking 
powders. 

Eochelle Salt. KNaC 4 H 4 6 +4aq. This salt is 
a double tartrate of potassium and sodium, which was 
formerly much used as a purgative. It may be pre- 
pared by mixing in a porcelain dish, 3500 grams of 
water and 1000 grams of cream of tartar, this is brought 
to boiling and sodium carbonate added as long as ef- 
fervescence is produced. This solution is then filtered 
and evaporated until it has a density of 1.38. 

The salt crystallizes in regular rhomboidal prisms; 
it is soluble in 2J- times its weight of water, but in- 
soluble in alcohol. 

Tartar emetic. Tartaric acid forms, with bases, a 



EMETICS. 119 

a class of salts called emetics, the type upon which 
they are formed being that of tartar emetic. The 
ordinary^ tartar emetic has been generally assigned the 
formula (SbO)'K=0 2 =C 4 H 4 04, in which the monad 
radicle stibyl takes the place of one of the basic hydro- 
gen atoms. It is prepared by boiling for an hour in 
100 parts of water, 12 parts of cream of tartar, and 10 
parts of antimony oxide. This mixture is then 
filtered, evaporated and allowed to crystallize. This 
salt crystallizes in rhombic octahedrons ; it has a me- 
tallic taste, a slight acidity, and is soluble in 14 parts 
of cold, and about 2 parts of boiling water. 

Crystals of tartar emetic effloresce on exposure to the 
air. 

A strip of tin precipitates the antimony as a brown 
powder. Tannin, and most astringents, precipitate 
the antimony, hence tartar emetic should not be ad- 
ministered in connection with this class of bodies. 
This salt is the most used of the antimony compounds. 

Feero -potassium taeteate. — Cream of tartar is di- 
gested with ferrous hydrate for two hours at a tem- 
perature of 60°. For every 100 parts of cream of tar- 
tar, a quantity of hydrate should be used containing 43 
parts of ferrous oxide. 

The product is filtered, the liquid received in shallow 
plates, and kept at a temperature of about 45°; the salt 
thus crystallizes in brilliant scales of a garnet red color. 
It dissolves in water, but is insoluble in strong alcohol. 
Tartaric acid is often adulterated with alum, potassium 
bisulphate and cream of tartar ; these substances may 



120 ORGANIC CHEMISTRY. 

all be detected by means of alcohol, in which they are 
not soluble. 

Tartaric acid is used in making effervescing drinks, 
and as a discharge by calico printers. 

Tartaric acid produces the same toxical effects as 
oxalic acid, though requiring much larger doses. The 
blood of the poisoned person becomes red and very 
fluid. 

CTTKIC ACID. 



nun — ^6H 4 3 ) ^ 



This acid is found associated with oxalic and tartaric 
acids in many plants. It occurs in cherries, currants, 
raspberries, oranges and lemons. 

It is ordinarily extracted from the juice of lemons. 
This juice is allowed to stand until fermentation com- 
mences, then filtered and treated with chalk and milk 
of lime ; an insoluble citrate of calcium is formed, which 
is decomposed by sulphuric acid; the calcium sul- 
phate is filtered off and the filtrate evaporated and left 
to crystallize. Citric acid crystallizes in regular 
rhombic prisms; it is soluble in three fourths its 
weight of cold water; this solution, in time, becomes 
covered with mould. 

Citric acid is soluble in alcohol and ether. Heated 
to about 175° it furnishes aconitic acid, 



C 6 H 6 6 = 



C 6 H 3 Oc 



}0 3 , 



CITEIC ACID. 121 

losing H 2 on increasing the temperature. Another 
pyrogenous acid, itaconie acid C 5 H 6 4 is formed, 
which, if heated, is transformed into citraconic acid 
isomeric with the last mentioned. 

Oxydizing bodies destroy citric acid, carbon dioxide, 
acetone, etc., being produced. Fused caustic potassa 
resolves it into acetic and oxalic acids. 

C 6 H A + H 2 0=C 2 H 2 4 + 2C 2 HA • 



Oxalic acid. Acetic acid. 

Citric acid is tetratomic and tri basic. It may be 
distinguished from oxalic and tartaric acids by its ac- 
tion on lime water, which it does not precipitate in the 
cold, but if boiled with an excess of lime water, a pre- 
cipitate of basic calcium citrate is obtained. 

Magnesium citeate. — This salt is prepared by treat- 
ing magnesium carbonate with a strong solution 
of citric acid and precipitating this salt with alcohol. 
It is much used in medicine as a purgative. 

Citrate of iron. — Hydrated ferric oxide is dissolved 
in a luke-warm solution of citric acid, and the liquid 
evaporated to dryness. 

This body varies in its composition ; it occurs in 
brilliant amorphous scales, of a garnet-red color. 

Ammonia cerate of iron. — One hundred grams 
citric acid are digested for some time with a quantity 
of ferric hydrate, representing 53 grams of iron, and 
16 to 20 grams of aqua ammonia. The liquid is then 
filtered and evaporated to the consistency of a syrup, 



122 ORGANIC CHEMISTRY. 

and transferred to very shallow vessels which are 
placed in drying ovens. This substance solidifies in 
scales, if the temperature at which it is dried is not too 
high and the layers of liquid are extremely thin. 

LACTIC ACID. 

C 3 H 6 3 = C 3 H 4 ) g 
H.H \ U ' 

This acid was discovered by Scheele, who extracted 
it from sour milk. It exists in many products after 
fermentation, as sauerkraut, beet juice, and various 
vegetables, also nux vomica. It is found in many ani- 
mal fluids, in the blood and in the fluids which per- 
meate the muscular tissues. It is to this body that the 
acid reaction of sour milk is due. Lactic acid extracted 
from flesh forms, with certain bases, salts which differ 
in solubility, etc., from those formed with ordinary 
lactic acid, hence this acid is sometimes called paralac- 
tic acid, also sarko-lactic acid, from Gapxo* flesh. 

Lactic acid may be prepared by dissolving sugar of 
milk in butter-milk, adding chalk to the mixture, and 
allowing it to stand for eight or ten days at a tem- 
perature of 30° to 35° 

The sugar of milk is sometimes replaced by glucose, 
or cane sugar and fermentation favored by the addi- 
tion of cheese. 

A special ferment (lactic ferment) is developed 
which is transformed into sugar and lactic acid, but 
the fermentation is arrested as soon as the liquid 



LACTIC ACID. 123 

becomes acid, and it is in order to prevent this acidity 
that an excess of calcium carbonate or sodium bicar- 
bonate is always maintained. 

Wurtz has produced this acid artificially by the 
action of platinum black on propylglycol. 

O a + CsIIsO.^CsHA + H 2 0. 



Propylglycol. 



Lactic acid is a colorless, syrupy liquid ; at about 
130° it is changed into the anhydride of lactic acid, 
C 6 H 10 O 5 , and at about 250° it furnishes a crystalline 
body called lactide whose formula is C 3 H 4 2 . 

Lactic acid posseses the property of dissolving cal- 
cium phosphate. The lactates are soluble in water. 
Lactate of iron, (C 3 H 5 3 ) 2 Fe, is employed in medicine. 

URIC OR LITHTC ACID, (^H^N^Oa. 

Discovered in 1716, by Scheele. 

This acid exists in human excretions, and in those of 
the carnivora. In the excretions of herbivora, the uric 
acid is replaced by hippuric acid. Uric acid is present 
in normal human urine only in small quantity. The 
urine of sedentary persons, and of those whose food is 
very nitrogenous and quite substantial, contains more 
of this substance than that of individuals who lead 
an active life, and whose diet is less nourishing. In 
the latter case the uric acid is oxydizecl and converted 
into urea, hence, the proportion of the acid decreases 
as the quantity of urea increases : whereas calculi of 



124 OEGANIC CHEMISTEY. 

uric acid are frequently formed in persons whose diet 
is very nourishing, and whose occupation necessitates 
but little muscular exertion. The excreta of birds 
contains a large proportion of uric acid, and that of 
snakes is formed almost exclusively of this body. 

This acid may be prepared by boiling a dilute al- 
kaline solution with guano, excreta of the boa con- 
strictor, or uric calculi finely pulverized. 

The liquid is filtered and the filtrate supersaturated 
with hydrochloric acid ; the uric acid precipitates in 
flakes, which become crystalline on standing. 

The author having had occasion in 1858 to prepare 
large quantities of uric acid from guano, found that in 
order to obtain the purest product, as free from color- 
ing matter as possible, it was preferable to use sod- 
dium hydrate as a solvent, and carbon dioxide as a pre- 
cipitant, the latter in sufficient excess to transform the 
hydrate into bicarbonate. 

. Crystals of uric acid are colorless and odorless. 
They are nearly insoluble in ether and alcohol. 
About 1500 parts of boiling water are necessary to 
dissolve one part of the acid. 

' On distillation uric acid yields urea and other cy- 
anic compounds. Uric acid heated with water and 
lead dioxide furnishes urea and a substance called al- 
lantoin, which has been found in the urine of sucking 
calves. Its formula is C 4 H 6 E" 4 3 . 

The same derivative of uric acid was obtained by 
the author in 1858, also parabanic acid, on heating uric 
acid with manganese dioxide and sulphuric acid. 
(80-[2]44-218.) 



URIC ACID. 125 

If 1 part of uric acid be added to 4 times its weight 
of nitric acid of a specific gravity of 1.45, the solution 
being kept cool, small crystals of a substance called 
alloxan separate out, whose formula is 

C 4 H 4 lSr 2 5 +3H 2 0. 

Woehler and Liebig obtained from this body a num- 
ber of very interesting derivations, alloxantin, al- 
loxanic acid, parabanio acid, thionuric acid, dia- 
luric acid, and finally a magnificent purple crystalline 
body, murexide. A large number of various deriva- 
tives have also been obtained by other chemists, 
especially Bayer. The rich color, murexide, is made 
use of in detecting uric acid. For this purpose, traces 
of uric acid are heated in a watch glass for a few 
minutes, with one or two drops of nitric acid ; the ex- 
cess of acid is evaporated, and the dry residue exposed 
to the vapors of ammonia, when a purple, or very 
beautiful rose color, will appear. 

HIPPURIC acid. 

C 9 H 9 N0 3 . 

The urine of herbivora contains a large percentage 
of this acid, which also exists in a small quantity in 
human urine. A frugivorous diet augments the pro- 
portion of this body. It is prepared by boiling the 
fresh urine of the horse (hence the name, from innos, 
a horse), or better from that of a cow, with milk of 



126 ORGANIC CHEMISTRY. 

lime, which is then filtered and evaporated to one- 
tenth its volume; this is mixed with a large excess of 
hydrochloric acid and left to stand 10 or 12 hours. 
The impure hippuric acid which precipitates is re-dis- 
solved in soda and re-precipitated with hydrochloric 
acid. Animal charcoal may be added to the saline so- 
lution if the brown color still remains. Putrid urine 
yields only benzoic acid. Dessaignes has prepared 
this acid artificially by causing zincic glycocol to act 
on benzoyl chloride. 

Zn(C 2 H 4 N0 2 ) 2 + 2C 7 H 5 0C1= 
ZnCl 2 + 2C 2 H 3 [NH(C 7 H 5 OJ0 2 . 

Hippuric acid crystallizes in colorless crystals, 
Avhich require 600 parts of cold water for their solution, 
but are very soluble in hot water and alcohol. 

It is decomposed at 240°, benzoic and cyanhydric 
acids being found among the products of distillation. 
Under the action of oxydizing agents it furnishes ben- 
zoic compounds; with nitrous acid it yields benzo-gly- 
colic acid. 



ALKALOIDS. 127 



ALKALOIDS. 

ARTIFICIAL BASES OK ALKALOIDS. 
PRIMARY. 

C n H 2n+3 N. 

Methylamine - - - CH 5 N 

Ethylamine - - - C 2 H 7 E" 

Propylamine - - ■ - C 3 H 9 N 

Butylamine - C 4 H n lS" 

Amylamine - - - C 5 H 13 N 

Caprylamine - - - 8 H 19 ]Sr. 

4 c n H 2n+1 isr. 

Acetylamine - C 2 H 5 N 

Allylamine - - - C 3 H 7 N. 

Plienylamine, aniline - - C 6 H 7 N 

Toluidine - C T H 9 N 

Xylidine - C 8 H U N 

Cumidine - C 9 H 13 N. 

C n H 2n _ 7 K 

Phtalidaimne - - - (lEUST. 



128 ORGANIC CHEMISTRr. 



C n H 2n _ n K 




Naphthalamine - 


(WN. 


SECONDARY. 




Dimethylamine 
Methylethylaraine - 
Diethylamine 


C 3 H 9 N 

C 4 H n K 


TEENAEY. 




Trim ethylamine 

Dimethylethylamine 

Methylethylamylamine 


C 3 H 9 ^ 
C 4 H n ^ 
C 8 H 9 K 


PHOSPHINES. 




Methylphosphine 
Dimethylphosphine 
Trimethylphosphine - 


CH 5 P 

• C 2 H 7 P 

C 3 H 9 P. 


AESINES. 




Triethylarsme 


C 6 H 15 As. 


STIBINES. 




Triethylstibine 


6 H 15 Sb. 



NATURAL ALKALOIDS. 129 

PKINCIPAL NATUKAL ALKALOIDS. 



OF THE CINCHONAS. 



Quinia,Quinicia and QumidiaQjoHyN^ 
Cinchonia and Cinchonidia O20H24N2O 
Aricina - - - CasH-j^C^. 





OF 


OPIUM. 




Morphia 




- 


c 17 H 19 isro3 


Codeia 


- 


- 


C 18 H 21 N 3 


Thebaia 




- 


C 19 H 21 N0 3 


Narcotina 


- 


- 


cano 7 


Papaverine - 




- 


CA^o 4 


Narceia 


- 


- 


C23H29N 9 . 


OF 


THE 


STEYCHNOS. 


Strychnia 


- 


- 


CaHaNA 


Brucia 


- 


- 


CJE{ 2 qN 2 0^ 


OF 


THE 


SOLANACE^E. 


Nicotina 




- 


CioH 14 E"2 


Atropia - 


- 


- 


0„H a N 3 


Hyosciamine 




- 


OnHaNO, 


Solania 


- 


- 


C 43 H n N 16 . 



OF THE HEMLOCK. 

Conylia - - - C 8 H 15 N. 



130 OEGANIC CHEMISTRY. 

OF PEPPER. 

Piperidine - - - C 5 H U K 

MISCELLANEOUS. 

Aconitina - - - C 2T H 40 1^ O 

Yeratria - - - C 32 H 52 K 2 8 

Theobromine - - C 7 H 8 N 4 2 

Caffeia - - - C 8 H 1Q N 4 2 . 

The first organic base isolated was morphia, obtained 
in 1816, by Sertuerner. In 1819, Pelletier and Ca- 
ventou extracted quiniafrom cinchona bark, and showed 
that the very active plants used in pharmacy owed their 
energy to compounds capable of uniting with the acids, 
and of forming with them definite crystallizable salts. 

From that epoch, the number of organic alkaloids has 
become very considerably augmented ; and methods 
have been discovered by which many of the alkaloids 
are prepared artificially, It was Fritsche who, in 
1840, obtained the first artificial alkaloid on distilling 
indigo with potassa ; he named it aniline. Gerhardt 
by similar methods prepared quinoleine, Cahours 
piperidine, and Chantard toluidine. 

The distillation of organic matter also furnishes al- 
kaloids. Thus several of them have been obtained 
from a product of the distillation of bones, the oil of 
Dippel ; also as products of the distillation of various 
other organic compounds. 



COMPOUND AMMONIAS. 131 

A very general method is due to Zinin, which, con- 
sists in causing a reducing substance to act upon 
nitrous compounds as nitrobenzol, for example. The 
nitrous compound is introduced into an alcoholic solu- 
tion of ammonium sulphide, and the mixture allowed 
to stand ; sulphur is soon deposited, and the hydrogen 
of the hydrogen sulphide combines with the oxygen 
of the nitrous compound. Example: 

C 6 H 5 N0 2 + 3H 2 S=2H 2 + 3S + C 6 H 7 K 

Nitrobenzol. Aniline. 

For this mode of reduction, as it is not very prac- 
tical, and is tedious in execution, there is at present 
substituted the action of iron upon acetic acid, or 
that of zinc or tin, on hydrochloric acid. 

Wurtz has given a very interesting method, which 
has led to the discovery of alkaloids much resembling 
ammonia, for that reason called compound ammonias. 
It consists in causing potassa to react upon the cyanic 
ethers, these bodies being decomposed much like cy- 
anic acid. 

Thus methylamine is obtained by the action of 
potassium hydrate upon cyanate of methyl : 

CO ) 0H s| 

^ s Vn+2Kho=k 2 co 3 + h [isr. 



Cyanate Potassium Methyl- 

of methyl. carbonate. amine. 

Hofmann made known, very shortly after the pub- 



132 



ORGANIC CHEMISTRY. 



lication of "Wurtz' process, a method for the prepara- 
tion of the compound ammonias, by which not only a 
simple equivalent of hydrogen is replaced by the 
radicles (CH 3 ), (C 2 H 3 ), etc., but all the hydrogen of 
the ammonia. Hofmann's method consists in causing 
ammonia to react upon hydrochloric as well as brom- 
hydric or iodhydric ethers, particularly the latter. 

Let us take, as an example, iodide of ethyl in con- 
nection with the study of 

ETHYLAMINE. 

Ten to 15 grams of iodide of ethyl and 50 grams of 
aqua ammonia are heated in sealed tubes of green glass 
placed in a water bath. The following reaction occurs: 

C 2 H 5 I + ]SrH 3 =C 2 H 8 NL 

When the liquid has become homogeneous it is 
allowed to cool, then decomposed by a solution of po- 
tassium h} r drate, the vapors being collected in water, 
containing hydrochloric acid. The hydrochloric acid 
solution is evaporated to dryness, and the residue treated 
with pure alcohol, which dissolves the chlorhydride of 
ethylamine and leaves in an insoluble state the ammo- 
nium chloride derived from the excess of ammonia 
used. The solution of chlorhydride of ethylamine is 
evaporated to dryness, and the deliquescent crystals 
obtained decomposed by potassium hydrate, with the 
aid of a gentle heat. The volatilized product is con- 
densed in a cooled receiver. In this reaction there is 



CLASSIFICATION OF THE ALKALOIDS. 133 

also formed diethylamine, triethylamine and oxide of 
tetrethylammonium from which the ethylamine is 
separated by distillation. 

It may be obtained more readily by first distilling 
1 part potassium cyanate with 2 parts potassium 
siilphovinate, then by decomposing the cyanic ether 
obtained with a boiling solution of potassium hydrate 
contained in a flask connected with a cool receiver. 

Ethylamine is a limpid liquid, with a strong odor 
resembling that of ammonia. It has not been solidi- 
fied. It boils at 18. 7°, and dissolves in water, producing 
a very caustic solution. Ethylamine is equally soluble 
in alcohol and ether. It is combustible, burning with 
a blue flame, yellow at the margin. 

It displaces ammonia from its combinations. Its 
solutions give reactions similar to those of ammonia; 
for instance, with salts of copper it gives a bluish white 
precipitate, which is dissolved in an excess producing 
a deep-blue solution. 

It differs from ammonia in the following reaction: 
ethylamine precipitates alumina from its salts, and 
the precipitate is soluble in an excess of ethylamine, 
which is not the case with ammonia. 

CLASSIFICATION OF THE ALKALOIDS, OK OKGANIC BASES. 

Amines. — Hofmann has given the names of primary 
amines, or monamines, to ethylamine, which we have 
just studied, and the compound ammonias in which a 
single atom of hydrogen has been replaced by a 
radicle. 



2 H 5 






( a H 5 


K 


+CJ3£= 


=N- 


2 H 5 ,H1 


H 






H 



134 ORGANIC CHEMISTRY. 

The same chemist, having prepared ethylamine by 
the action of ethyl iodide upon ammonia, subse- 
quently succeeded in obtaining diethylamine by similar 
means. 

The reaction is the following : 



N 



This hydroiodide obtained, treated with potassium 
hydrate or lime, furnishes a second base, which is 
biethylammonia, or diethylamine ; 

Diethylamine C 4 H 11 ^"=:]Sr 
A similar compound is, 

f H TT 

Ethylaniline C 8 H n N=N"^ C 3 hJ. 

l-H 

These bases have been given the name of secondary 
amines or imides. 

The secondary ammonias are attacked by ethyl iodide 
and other ethers, and a reaction takes place, iden- 
tical with that which gives rise to the primary and 
secondary amines and tertiary amines, also called 
nitrile bases, are thus obtained. 




AMINES. 135 

Such bodies are: 

fC 2 H g 
Trietkylamine C 6 H 15 N=:N^ C 2 H 5 . 

tC 2 H s 

fCH 3 
Methylethylphenylamine C 9 H 13 N=N^ C 2 H 5 . 

IC 6 H 5 

These bases are related to the alcohols in the same 
manner as the primary amines. Thus diethylamine is 
derived from the action of 2 molecules of alcohol on 1 
molecule of ammonia and the elimination of 2 mole- 
cules of water: 

2(C 2 H 6 0) + NH 3 -2H 2 0=C 4 H u ]Sr. 

In like manner the ternary amines may be consid- 
ered as derived from 3 molecules of alcohol and 1 mole- 
cule of ammonia with the elimination of 3 molecules 
of water. 

There are also bodies built upon the type of two 
and three condensed molecules of ammonia, and are 
denominated, respectively, di-amines and tri-amines; as 

( (C 2 H 4 )" 
Secondary ethylene diamine N 2 < (C 2 H 4 )' ; , 



H 



IT 
4 ' 



Ternary ethylene diamine N 2 •< (C 2 H4)\ 

I (0 2 H 4 )" 



136 ORGANIC CHEMISTRY. 

Trieth ylamine attacks hydroiodic ether, and there is 
formed the compound C 8 H M NI=]S"(C 2 H 5 ) 4 L This 
body treated with oxide of silver, furnishes an oxy- 
genated quaternary base, 

CsH^JSTI + Ag HO=Ag I + C 8 H 21 NO. 

This substance is very caustic, soluble in water and 
acts as an in organic alkaline base like potassium 
hydrate, with which body it is also analagous in com- 
position. 

KJ Q (W| a 

Amides, Alkalamides. — The amides are bodies built 
upon the type of ammonia, in which one or more of the 
hydrogen atoms are replaced by an acid compound 
radicle; thus, 

( C 2 H s O 

acetamide IIH . 

(H 

There are also mixed combinations of amides and 
amines, called alkalamides, as 

C 6 H 5 
acetanilide N" ■{ C 2 H 3 0. 
H 



ALKALOIDS. 137 



JSTATUEAL ALKALOIDS. 

Many of the natural alkaloids appear to possess a 
composition analogous to that of the compound am- 
monias. Some are not attacked by iodide of ethyl, 
and should be classified among the ammoniums, bodies 
having the same relation to the compound ammonias 
as does ordinary ammonium hydrate to ammonia. 
Others are acted upon by iodide of ethyl, and, from the 
number of bases furnished, it may be ascertained 
whether they belong to the primary, secondary or ter- 
nary compound ammonias. 

The properties of the natural alkaloids in general, 
resemble those of the artificial bases or alkaloids. 
They contain nitrogen ; those that do not contain oxy- 
gen are ordinarily volatile, while those with oxygen are 
non- volatile ; they are very soluble in alcohol, ether 
and chloroform. 

Certain ones are dissolved by the hydrocarbides, 
which are now considerably used in the preparation of 
the alkaloids. Water does not dissolve any of the 
artificial alkaloids, except those having a very low 
molecular weight, like ethylamine; this liquid, how- 
ever, dissolves codeia and narceia quite readily. With 
the exception of quinia and cinchonia, they turn the 
plane of a polarized ray of light to the left. 

They react like ammonia, or potassa, with vegetable 



138 ORGANIC CHEMISTRY. 

colors, and furnish, with platinum bichloride, crystal- 
lizable double chlorides, little soluble and yellow in 
color. They combine equally well with auric and mer- 
curic chlorides. 

The natural alkaloids have ordinarily a bitter taste. 
Among their salts the sulphates, nitrates, chlorides 
and acetates are mostly soluble, while the oxalates, 
tartrates and tannates are insoluble. 

The harmless character of tannic acid, and the in- 
solubility of the compounds formed by it, with the al- 
kaloids, render tannin and astringent vegetable sub- 
stances generally very efficacious antidotes. 

The precipitates they produce are soluble in acid and 
alkaline liquids. 

The alkaloids are partially precipitated from their 
solutions by potassa, soda and ammonia. Iodine water 
and solutions of iodine in potassium iodide, precipitate 
them completely. 

According to Schultze, the liquid obtained by add- 
ing antimony perchloride to a solution of phosphoric 
acid, is a re-agent which precipitates most of the or- 
ganic bases. 

A delicate re-agent for the alkaloids is the double 
iodide potassium and mercury. According to Meyer, 
the best proportions are 49 grams of potassium iodide 
and 135 grams of mercury dichloride, to 1 litre of 
water. It is best to add the re-agent to xhe solution 
of the alkaloid, which may be neutral, acid, or even 
feebly alkaline. 

It must be borne in mind that the presence of 



NICOTINA. 139 

sugar, tartaric acid and of albumen may mask the reac- 
tions of a number of alkaloids. 

NICOTINA OR NICOTYLIA. 

C 10 H 14 N 2 . 

Nicotina is obtained from tobacco (Nicotina taba- 
cum.) For this purpose a decoction of tobacco is made, 
and the liquor evaporated to a syrup. The extract is 
treated with twice its volume of 85 per cent, alcohol, 
which precipitates the salts present and certain organ- 
ic substances. 

. The alcoholic solution is distilled and the residue 
submitted to a second similar treatment. The alco- 
holic extract thus obtained, is mixed with a concen- 
trated solution of potassium hydrate, and the nicotina 
liberated is re-dissolved in ether. This ethereal solu- 
tion is evaporated in a water bath, and the residue 
distilled in an oil bath, in an atmosphere of hydrogen. 

Nicotina is a colorless liquid when pure, remaining 
liquid at -10°, boiling at about 215°, with decomposi- 
tion. It has the odor of an old pipe. Exposed to 
the air it becomes brown, then resinous; water, alcohol 
and ether dissolve it ; its solutions are strongly 
levogyrate. 

Nicotina is a powerful base; it fumes when a rod 
moistened with hydrochloric acid is brought near it; 
it precipitates the metallic oxides. Nicotina requires 
two molecules of a monobasic acid for saturation. 
The chloride, C 10 H 14 N 2 ^HC1, is crystallizable, though 



140 ORGANIC CHEMISTRY. 

deliquescent. The hydrogen it contains is not replace- 
able by methyl, ethyl, etc. It may be considered as 
having the rational formula, 

iri(<W' 

iN2 l(C 3 H,)'"; 

(C 5 H 7 ) ' ' ' being the compound radicle nicotyl. 
Proportion of nicotina in different tobaccos : 

Havana, - - 2.0 per ct. 

Maryland, - - 2.3 " 

Yirginia, - - 6.9 " 

Lothringen, - - 8.0 " 

(Schloesing.) 

POISONING BY TOBACCO OK BY NICOTINA. 

The injection of a concentrated decoction of tobacco, 
causes serious results in a few minutes : intense head- 
ache is produced, with nausea and vomiting, violent 
pain in the abdomen, pallor, and, finally, extreme 
prostration. 

An infusion of tea, unroasted coffee, or any astring- 
ent substance (pulverized nut-galls, or oak-bark) are 
the only antidotes known, and they are far from being 
wholly reliable. 

The pure nicotina is one of the most dangerous 
poisons. It manifests itself immediately on being 
taken, since it is entirely soluble in water. 

The nervous system is especially affected. Two or 
three drops suffice to cause death. 



COJN"IA. 141 

Two drops introduced into the throat of a dog will 
almost instantaneously cause the following series of 
symptoms : respiration becomes difficult, the animal 
staggers, falls without the power of rising again, 
throws the head back and, in a few moments, is perfect- 
ly paralyzed, and death ensues. 

PIPERIDINE. 

5 H u N. 

There has been obtained from the pepper ( Piper 
longum, Piper nigrum or Piper caudatum), a body- 
crystallizing in colorless prisms called piperine, whose 
formula is C 1T H 19 ]Sr0 3 . It is a neutral substance. 
When distilled with three times its weight of soda- 
lime it furnishes piperidine, a limpid liquid having 
the taste of pepper, and also its odor, soluble in water 
and alcohol, boiling at 106°. 

This body is alkaline and saturates acids. It con- 
tains a single atom of hydrogen replaceable by methyl, 
ethyl, etc. 

CONIA, CONYLIA, OK CONINE. 

c 8 h 15 k 

This body is obtained from hemlock (Oonium mac- 
ulatum); the crushed seeds are distilled in a large glass 
retort, with a solution of potassa, or soda, whereupon an 
alkaline distillate is obtained. The distilled product is 
treated with a mixture of two parts of alcohol and one 



142 ORGANIC CHEMISTRY. 

part of ether, which dissolves the sulphate of conia and 
leaves the insoluble sulphate of ammonium. The ethe- 
real alcohol is separated by distillation, potassa is added 
to the residue, and the mixture distilled. Water and 
coma pass over ; the latter is dehydrated with po- 
tassa, and rectified in vacuo, or in a current of hydro- 
gen gas. 

Conia is a colorless, oily liquid; emitting an odor 
of hemlock. "Water dissolves it but little, and this 
better when cold than warm. It is very soluble in al- 
cohol and ether. It boils at about 210°, yet emits va- 
pors even when cold, for if a glass rod, moistened with 
hydrochloric acid, is brought near it, white fumes are 
produced. It is a monacidic base, Yery alkaline, and 
forms crystallizable salts. One of its atoms of hydro- 
gen is replaceable by ethyl or methyl. 

This base is very poisonous. According to Christi- 
ason, ten centigrams would suffice to cause death. It is 
classified among the narcotics; its action is charac- 
terized particularly by its effect on the organs of respi- 
ration and the left ventricle of the heart. 

ALKALOIDS OF THE PAPAVERACEJ3. 

The poppy-seed capsules ( Papaver somniferum) 
yield, on incision, a milky sap, which dries up in a day 
or two ; this sap, when solidified, constitutes opium. 
There are three leading varieties of opium : 

I. Opium of Smyrna is found in small cakes of 
100 to 150 grams, frequently distorted and agglutinated 
together by reason of their soft nature, and contain 7 



opium. 143 

to 10 per cent, of water. The surface is brown, but the 
interior has a fawn color. Sometimes it is found to 
contain 14 to 15 per cent, of morphia, but in other in- 
stances only 5 to 6. Good Smyrna opium should con- 
tain not less than 10 per cent. 

II. The opium of Constantinople is drier than the 
preceding. It appears in commerce in flattened, irreg- 
ular cakes, almost always surrounded with poppy- 
leaves. It contains 5 to 10 per cent, of morphia. 

III. The opium of Egypt is still dryer ; it is rarely 
enveloped in leaves. Its odor is feeble, and it contains 
no more than 2 to 7 per cent, of morphia. 

Recently, attempts have been made to cultivate the 
poppy in Europe, especially in France. 

Opium contains the alkaloids morphia, codeia, the- 
baia, papaverine, opianine, narcotine and narceia, an 
acid combined with these alkaloids called meconic acid 
(from fArjKGjv, a poppy), a crystallized neutral substance 
called meconine, which, according to Berthelot, is a 
complex alcohol, and finally, various gummy and resin- 
ous compounds. 

MORPHIA OR MORPHINE. 

C K H 19 NO s , H 2 0. 

Preparation. Ten kilos, of opium are treated re- 
peatedly with water, and the liquors evaporated to the 
consistency of a syrup. 

The mass is redissolved in water, filtered, and again 
evaporated. To the lukewarm liquid are added 1200 



144 OKGANTC CHEMISTEY. 

grams of anhydrous calcium chloride, dissolved in 
twice its weight of water. A complex precipitate is 
formed, containing resins, coloring matters, and sul- 
phate and meconate of calcium, which is thrown upon 
a filter. 

The filtered liquid is evaporated over a water-bath. 
During the concentration, a fresh quantity of meconate 
of calcium is separated by filtering, and the liquid 
evaporated to the consistency of syrup. The liquid is 
then acidulated with a small quantity of hydrochloric 
acid, and set aside in a cool place. 

At the end of a few days, it contains brown crystals 
of the double chlorhydrate of morphia and codeia, con- 
taminated with a blackish liquid ; these crystals are 
drained, pressed, and again dissolved in as little boil- 
ing water as possible. The chlorhydrate, on cooling, 
deposits crystals, which are again dissolved in hot 
water and decolored with animal charcoal. After 
heating to 80° or 85°, the solution is filtered, and the 
liquid, on being concentrated, deposits the double chlor- 
hydrate in pure white crystals. 

This salt is again dissolved in boiling water, and the 
hot liquid treated with ammonia ; the codeia remains 
in solution, while the morphia is precipitated. This 
deposit is thrown upon a filter washed with cold water, 
dried, and dissolved in boiling alcohol ; the morphia 
separates out in crystals on cooling. 

It frequently contains some narcotina, from which 
it is freed by washing once or twice with ether, or 
chloroform, which dissolves the narcotina, and does 
not affect the morphia. 



MORPHIA. 145 

Pure morphia, (from Morpheus, in allusion to its nar- 
cotic qualities,) crystallizes in regular prisms with a 
rhombic base, is colorless, soluble in 500 parts of boil- 
ing water, scarcely soluble in cold. Forty to forty-five 
parts of cold 90 per cent, alcohol are required to dis- 
solve one part of morphia ; it is insoluble in ether. 
Solutions of morphia are very bitter. 

Morphia is little soluble in ammonia, while it is dis- 
solved very readily by alkaline solutions, and even by 
lime water. 

Under the action of heat, it fuses in its water of 
crystallization, the latter escaping, and the alkaloid re- 
crystallizes on cooling. 

Morphine is an energetic reducing agent, reducing 
gold and silver salts, setting free the respective metals. 
It separates the iodine from solutions of iodic acid. 
If a solution of starch is poured into a test-tube, and a 
solution of iodic acid and traces of morphia added, the 
blue color of iodide of starch appears. 

If morphia is put into a few drops of a concentrated 
and slightly acid solution of a ferric salt, a beautiful 
blue color is produced, which subsequently changes to 
green. 

Morphia, moistened with nitric acid, is colored 
orange-red, which rapidly changes to yellow. 

These four reactions are characteristic of morphia. 

If iodine and morphia are mixed in equal propor- 
tions and the mixture treated with boiling water, a 
brown liquid is formed which deposits a reddish-brown 
powder called iodomorjphia. Morphia fused with al- 



146 ORGANIC CHEMISTRY. 

kalies yields methylamine. (p. 127). It is attacked by 
ethyl iodide at 100°, a single molecule of ethyl 
entering into the group. 

Morphia forms crystallizable salts, from the solutions 
of which it is precipitated by the fixed alkalies. 

Chlorhydrate of morphia, C 1T H 19 E"0 3 B[C1+3H 2 0. 
To prepare this salt, 100 parts of pulverized morphia 
are treated with a little warm water, then hydrochloric 
acid is added in sufficient quantity to dissolve the al- 
kaloid. The solution is afterwards evaporated in a 
water bath until it crystallizes. 

This salt is soluble in 20 parts of cold water, very 
soluble in alcohol. It is the salt of morphia most 
used, and contains 76 per cent, of morphia. 

Sulphate of morphia, (C 17 H 19 J s n"0 3 ) 2 II2S04+5II 2 
is prepared like the preceding salt, which it resembles 
in appearance as well as in properties. 

Morphia and its salts are used in very small doses, 
as in larger doses they are energetic poisons. 

Codeia, dgHaNOsjHaO. 

Discovered in 1832 by Robiquet. This base, whose 
name is derived from kgdStj^ poppy head, exists in the 
ammoniacal solution obtained in the preparation of 
morphia. On evaporation the ammonia is driven off 
and the codeia is precipitated by potassa. The codeia 
is at first precipitated in the form of a sticky mass 
which soon becomes pulverescent. It is washed with 
and dissolved in hydrochloric acid. The liquid is then 
boiled with washed animal charcoal, and the codeia 
precipitated with potassa. 



NAKCOTINA. 147 

Codeia is crystalline, very soluble in alcohol and 
ether. It dissolves in 80 parts of cold and in 20 parts 
of boiling water. 

Codeia is very soluble in ammonia, and nearly in- 
soluble in potassa. With chlorine, bromine and ni- 
tric acid it forms products of substitution. "With 
iodine it furnishes ruby-red crystals, whose formula is 

c 18 H 21 ]sro 3 i. 

Codeia is somewhat used as an anodyne. It is easily 
distinguished from morphia, since: 

I. Codeia is soluble in ether and ammonia. 

II. It is insoluble in solutions of potassa. 

III. It does not reduce iodic acid or ferric salts. 

IV. Nitric acid does not impart to it any color. 

Narcotina, CasILjgNO?. 

Narcotina crystallizes in rhombic prisms. It is al- 
most insoluble in cold water, somewhat soluble in 
alcohol, quite so in ether. It fuses at 170°, and is 
decomposed before reaching 200°. Dilute nitric acid 
transforms it into various products of oxydation, the 
most important of which are meconine, cotarnine 
and ojpianie acid !Narcotina unites with acids, but 
the compounds are decomposed on evaporation. 

It is distinguished from morphia in that it does not 
reduce iodic acid and ferric salts, and from codeia in 
giving with nitric acid a blood red coloration. This 
substance is also insoluble in potassa and ammonia. 
It is not as poisonous as morphia. 



148 ORGANIC CHEMISTRY. 

THEBAIA. 

C 19 H 21 X0 3 . 

This alkaloid, sometimes called paramorphia, is the 
most poisonous of the bases of opium. 

It is crystallizable, insoluble in water, soluble in 
alcohol and ether. Fuming nitric acid attacks it in 
the cold, and a yellow liquid is obtained, which be- 
comes brown on contact with alkalies, and which dis- 
engages an alkaline vapor. Concentrated sulphuric 
acid gives it a red hue. 

PAPAVERINE. 

This body is crystallizable, insoluble in water, quite 
soluble in boiling alcohol and ether. It forms crystal- 
line salts. 

Under the action of strong sulphuric acid it as- 
sumes a deep blue color, though Hesse and Drag- 
endorff have recently ascertained that when absolutely 
pure no color is obtained, the ordinary article found 
in trade not being pure. 

NAECEIA. 

gwbustcv 

This alkaloid crystallizes in silky needles, insoluble 
in ether, soluble in alcohol and boiling water, little 
soluble in cold water. It forms crystallizable salts. 



opium. 149 

Narceia fuses at 95°, and commences to decompose 
at about 110°. It is attacked in the cold by concentrated 
sulphuric acid, a red liquid being produced which 
rapidly becomes green, especially if slightly heated. 
The best means of distinguishing narceia is to cause a 
solution of iodine to act upon the pulverized substance. 
According to Roussin, the operation is most easily per- 
formed with one part of iodine and two parts of potas- 
sium iodide dissolved in ten parts of water. A blue 
color is produced, which disappears on coming in con- 
tact with alkalies, or on heating. 

PHYSIOLOGICAL ACTION OF OPIUM. NARCOTIC POISONS. 

Opium in small doses is a very highly-prized ano- 
dyne. Continued use of this substance produces a 
peculiar state of inebriation, an excited sleep and hal- 
lucinations of various sorts. 

The bodies of opium-eaters are lean and cadaverous, 
their eyes are lustrous, their forms bent; their appe- 
tite diminishes, and they exist only by increasing the 
dose of the poison which destroys them. In larger 
doses it is highly poisonous, and acts in a different 
manner from that of the poisons already studied. It 
may be considered as the type of the narcotic poisons. 
It is not unfrequently used for criminal purposes, 
and the imprudent administration of laudanum and 
other solutions of this substance often causes serious 
effects. 

Claude Bernard has made a careful study of the ac- 
tion of the various alkaloids of opium upon the system, 



150 



ORGANIC CHEMISTRY 



and has tabulated their soporific, toxic, and convulsive 
actions as follows : 



Toxic. 



Thebaia, 

Codeia, 

Papaverine, 

Narceia, 

Morphia, 

Narcotina. 



Convulsive. 

Thebaia, 

Papaverine, 

Narcotina, 

Codeia, 

Morphia, 

Narceia. 



Soporific. 

Narceia, 
Morphia, 
Codeia. 



With- 
out 
action. 



Those at the head of each column are the most 
marked in the respective characteristic action. 

Subjoined are tabulated the principal chemical 
characteristics of the opium alkaloids : 





"WATER. 


ALCOHOL. 


ETHER. 


AMMONIA.. 


Morphia. 


Bat little sol- 
uble. 


Quite soluble. 


Almost insol- 
uble. 


Nearly insol- 
uble. 


Codeia. 


Soluble. 


Very soluble. 


Very soluble. 


Soluble. 


Narcotina. 


Insoluble. 


Soluble. 


Soluble. 


Insoluble. 


Thebaia. 


Insoluble. 


Soluble. 


Soluble. 


Insoluble. 


Papaverine. 


Insoluble. 


Soluble. 


Soluble. 


Insoluble. 


Narceia. 


Slightly soPble 


Soluble. 


Insoluble. 


Insoluble. 



QUINIA. 
QTJINIA OK QUININE. 



151 



C^H^ 2 2 ,3H 2 0. 

This alkaloid was discovered in 1820 by Pelletier 
and Caventou. The following is the modern process 
bj which it is prepared. 

Yellow Peruvian bark is carefully pulverized and 
thoroughly mixed with 30 per cent, of its weight of 
lime, previously slacked. The mass is then lixiviated 
three or four times with refined petroleum (petroleum 
ether) or amy lie alcohol, (wood spirit) which dissolves 
the alkaloids. 



NITRIC ACID. 



SULPHURIC ACID. 



IODIC ACID. 



Soluble. 

Nearly insoluble. 

Insoluble. 
Insoluble. 

Insoluble. 
Insoluble. 



Orange-red color- 
ation. 



Orange-red color- 
ation, 

Blood -red color- 
ation. 

Yellow coloration. 



Colored violet on 
beating with di- 
lute acid. 

Colored violet on 
heating with di- 
lute acid. 

Yellow coloration. 

Eed coloration. 

Dark- blue color- 
ation. 

Red color, which 
becomes green. 



Reduced. 

Is not reduced. 
Is not reduced. 



152 ORGANIC CHEMISTRY. 

The united extracts are agitated with water, acidu- 
lated with sulphuric acid, making the liquid only 
slightly acid. 

When the solution is completed, animal charcoal is 
added, and the liquid brought to boiling, filtered while 
still hot, and allowed to cool. The quinia sulphate 
which is formed, 2(C 20 H 24 ]^ 2 O 2 ), H 2 S0 4 +7aq., being 
but slightly soluble, is deposited on cooling. 

After being allowed to stand 24 hours, the sulphate 
is collected, expressed and redissolved in as small a 
quantity of water as possible, containing a few drops 
of sulphuric acid. 

The liquid on cooling, deposits crystals, which are 
dried at 35°. The mother liquors are treated with 
ammonia, or sodium carbonate, which precipitates a 
certain quantity of the alkaloid. The precipitate is 
lightly washed with water, redissolved in dilute sul- 
phuric acid, boiled with washed animal charcoal, and 
allowed to cool. A second crop of crystals of quinia 
sulphate is thus obtained. The mother liquor contains 
cinchonia sulphate. This sulphate is dissolved in 30 
times its weight of boiling water, allowed to cool, and 
a slight excess of ammonia added. 

The cinchonia which is precipitated is collected on 
a filter, and washed with lukewarm water until the 
filtrate no longer gives with barium chloride a white 
precipitate insoluble in acids; it is then dried at a 
temperature of 30° to 40°. 

Quinia is white, amorphous and very friable. It 



SULPHATES OF QUI1NTA. 153 

may be obtained in a crystalline condition, by adding 
an excess of ammonia to a dilute solution of quinia 
sulphate, and allowing the solution to stand. 

This crystallized quinia melts at 57°, losing its water 
of crystallization, solidifies and remelts at 176°. It 
requires 250 parts of boiling and 460 parts of cold 
water for its solution. 

It dissolves in 2 parts of boiling absolute alcohol, 2 
parts of chloroform or 50 to 60 parts of ether. Its 
solutions are very bitter, levogyrate, and for the most 
part fluorescent. 

Heated on platinum foil, quinia swells up and in- 
flames, leaving a deposit of carbon. Heated with po- 
tassa it produces hydrogen and quinoleine; (cinchon- 
lein); it also furnishes a brown compound on being 
triturated with iodine. 

Quinia is recognized by the following reactions. It 
is first saturated with very dilute sulphuric acid and 
chlorine water; then an excess of ammonia is added, 
whereupon a green color is obtained. 

On adding powdered potassium ferrocyanide before 
the aqua ammonia a rose coloration is produced, which 
afterwards becomes dark red. 

Quinia has a basic reaction; it forms with acids 
crystallizable salts from which the alkalies precipitate 
quinia. It is a base which saturates two molecules of 
a monobasic acid. 

Sulphates of Quinia. Two sulphates of quinia are 
known; that obtained by the process we have above 



154 ORGANIC CHEMISTRY. 

described, is the neutral sulphate, though generally 
known as the basic sulphate. Its formula is 

2C 20 H 24 ]Sr 2 O 2 .H 2 SO 4 +7H 2 O. 

This salt contains 74.3 per cent, of quinia. 

It crystallizes in very delicate needles belonging to 
the clinorhombic system, and which effloresce in dry 
air. It dissolves in 30 parts of boiling and 740 parts 
of cold water ; also in 60 parts of cold absolute alco- 
hol. It is very nearly insoluble in ether. Its solu- 
tions are extremely bitter. It becomes phosphorescent 
on being heated, and subsequently fuses. 

Heated in the air it burns, leaving a carbonaceous 
residue. 

On adding quinia to water acidulated with sulphuric 
acid, it rapidly dissolves and another sulphate, often 
called the acid sulphate, is formed, whose formula is 

C 20 H 24 lSr 2 O 2 ,H 2 SO 4 + 7H 2 O. 

It is on account of the difficult solubility of the pre- 
ceding salt, and the great solubility of this latter one, 
that we cautioned against the employment of an excess 
of sulphuric acid in the preparation of quinia. 

This salt dissolves in 11 parts of water at 12°, and 
in 9 parts at 18°. Sulphate of quinia, heated to 130° 
with acidulated water for several hours, is transformed 
into an isomeric dextrogyrate base called quinicine, 
Which is likewise a febrifuge. 

Medicinal sulphate of quinia always contains sulphate 



QUINIA. 155 

of cinchonia, and its presence is not considered fraudu- 
lent, even when it contains 3.5 per cent, of the latter 
substance, as this salt is necessarily produced in the 
preparation of quinia. Cinchonia appears to be of little 
therapeutic value, and is often added to sulphate of 
quinia. 

This adulterant is detected by weighing out 0.5 
grams of the salt, and adding to it 5 grams of ether. 
The mixture is agitated and 1.5 grams of concentrated 
ammonia added. If no cinchonia is present, two liquid 
layers are obtained ; if it is present, a layer of this al- 
kaloid is formed directly above the ammonia. Good 
commercial sulphate of quinia should give only a very 
thin layer. 

The amount of quinia may be directly determined 
by decanting and evaporating the ethereal solution, 
and weighing the residue. This result may be verified 
by replacing the ether in another determination, by 
chloroform, which dissolves both bases; the residue 
obtained by the evaporation of this liquid furnishes the 
weight of the quinia and cinchonia together. 

Sulphate of quinia sometimes contains sulphate of 
quinidia; this base is precipitated, together with cin- 
chonia, by ether. Its presence may be detected by 
dissolving one gram of the sulphate in 30 grams of 
boiling water, and adding to the solution ammonium 
oxalate. Oxalate of quinidia, which is the only soluble 
oxalate of these bases, remains in solution, and, on fil- 
tering, a bitter liquid will be obtained, in which the 
quinidia may be precipitated by ammonium hydrate. 



156 ORGANIC CHEMISTRY. 

In case sulphate of qiiinia has been adulterated with 
calcium sulphate, or other inorganic substance, it may 
be recognized by a residue which will be obtained on 
heating the sulphate to redness on platinum foil. 

Sulphate of quinia should dissolve in 80 per cent. 
alcohol. If it dissolves in water, but does not dissolve 
in 56 per cent, to 60 per cent, alcohol, it may be re- 
garded as not pure. 

If adulterated with starch, or fatty bodies, a clear 
solution cannot be obtained, even in very large quanti- 
ties of water. 

Should it contain sugar it will emit an odor of 
caramel on ignition, and blacken in contact with sul- 
phuric acid. 

Quinia sulphate to which salicin, a common adulter- 
ant, has been added, is colored red by sulphuric 
acid. 

Quinia sulphate is chiefly employed in cases of in- 
termittent fevers. 

CINCHONIA OR CINCHONINE. 

C2oH 24 X 2 0. 

Cinchonia was discovered by Duncan in 1803, though 
first recognized as an organic base by Pelletier and 
Caventou in 1820. 

It differs from quinia in containing one atom less of 
oxygen ; it has never been converted into quinia. 

It is prepared in the same manner as quinia, but 



CINCHOFIA. 157 

from the Gray Peruvian Bark. Cinchonia separates 
out in crystals on the evaporation of the alcohol with 
which the calcic precipitate is washed. 

The crystals of cinchonia are collected, allowed to 
drain, and the liquid which runs off will furnish addi- 
tional crystals on being evaporated. To this mother 
liquor sulphuric acid is added in excess, and the solu- 
tion slightly evaporated. 

The first crystals obtained are sulphate of quinia, 
which is less soluble than sulphate of cinchonia. 
When nothing remains but a very concentrated mother- 
liquor, the cinchonia is precipitated by ammonia, and 
freed from quinia by washing with ether. The quinia 
dissolves, while the cinchonia remains insoluble. 

The latter crystallizes in brilliant colorless crystals, 
which are insoluble in cold water and ether, soluble in 
2,500 parts of boiling water, in 30 parts of boiling 90 
per cent, alcohol, and 40 parts of chloroform. 

Its solutions are very bitter and dextrogyrate. 

Cinchonia melts at. about 257°; on heating to a 
slightly higher temperature in a current of nitrogen, 
or hydrogen, it is completely sublimed. 

"With chlorine and bromine, it furnishes dichloride 
and dibromide of cinchonia. With iodine, a yel- 
low crystalline body is obtained, whose formula is 
CsoH^OI. 

Heated with fused potassa, it produces quinoleine. 

Cinchonia has an alkaline reaction. It unites with 
acids, forming salts which correspond to the salts of 
quinia, though generally more soluble. 



158 ORGANIC CHEMISTRY. 

Cinchonia sulphate, heated to about 135°, furnishes 
the sulphate of an isomeric alkaloid, cinchonicia or 
cinchonicine. 

Ciuchonia is employed as a febrifuge in Holland, and 
a few other countries, but its action is regarded as in- 
ferior to that of quinia. 

Qttixoidine. — Quinidia is a base obtained from the 
last mother-liquor in the preparation of quinia, by 
precipitation with sodium carbonate. It is often min- 
gled with another alkaloid, cinchonidia or cinchoni- 
dine, and it is this mixture, containing chiefly quinidia, 
which is called quinoidlne in commerce. 

Quinidia is isomeric with quinia ; it melts at 160°. 
It is difficultly soluble in water, very soluble in boil- 
ing alcohol, and slightly soluble in ether. Its solutions 
are dextrogyrate. Quinidia acts as a febrifuge. With 
chlorine and ammonia, it gives the same reactions as 
quinia, and forms corresponding salts. 

Quinoidine contains, as we have said, cinchonidia, a 
substance isomeric with cinchonia. This body is crys- 
talline, fusible at about 150°, almost insoluble in water, 
slightly soluble in ether and chloroform ; boiling alco- 
hol is the best solvent for cinchonidia. 






STRYCHNIA. 159 



ALKALOIDS OF THE STKYCHKOS. 

The two chief alkaloids are strychnia and brucia. 
Desnoix extracted from the nux vomica another alka- 
loid, which he named igasuria ; but according to 
Schutzenberger, this body is a mixture of several 
bases. 

These alkaloids are extracted from the fruit of the 
Strychnos nux vomica ; from St. Ignatius' beans, fruit 
of the Strychnos Ignatii ; from the wood of Coulevre, 
root of the Strychnos colubrina ; from the upas, the 
poison of indian arrows, extracted from the Strychnos 
tieutS) from the False Angustura Bark, also from the bark 
of the Strychnos nux vomica, which contains princi- 
pally brucia. 

STRYCHNIA. 

C21H22N202. 

Nux vomica is pulverized and boiled with three suc- 
cessive portions of water containing sulphuric acid, and 
these decoctions evaporated in a water bath. When 
the liquid is reduced to a small volume, 125 grams of 
quicklime slacked to a thin paste are added for each 



160 ORGANIC CHEMISTRY. 

kilo, of mix vomica. The precipitate is collected on a 
cloth, washed, dried, and treated with 90 per cent, al- 
cohol. 

The alcoholic solution is distilled to three-fourths its 
volume and left to crystallize. The crystals obtained 
are chiefly strychnia ; these are allowed to drain, then 
dissolved in water containing fa its weight of nitric 
acid, and the solution concentrated in a water bath. 

The nitrate of brucia remains dissolved and the 
nitrate of strychnia crystallizes out. These crystals 
are re-dissolved in water, animal charcoal added, the 
solution brought to boiling and then filtered. 

Ammonia is added to this liquid, the precipitate 
washed, dried, and dissolved in boiling alcohol, which 
deposits the alkaloids on cooling. 

This method is at present very advantageously sup- 
planted by the process given for the production of 
quinia, which, briefly stated, consists in treating the sub- 
stance with lime directly and employing a solvent for 
the alkaloids, which is insoluble in water, such as petro- 
leum or amy lie alcohol. 

Strychnia crystallizes in octahedrons or in prisms of 
the rhombic system; they are colorless, very bitter, and 
almost insoluble in water or ether, but readily soluble 
in ordinary alcohol diluted with 75 per cent, of water. 
Strychnia treated with potassa furnishes a small quan- 
tity of quinoleine. Iodide of ethyl produces with this 
base the compound . 



BRUCIA. ]61 

Chlorine gas renders even a dilute solution of this 
alkaloid turbid and the liquid becomes acid; this 
reaction is characteristic. Bromine also forms deri- 
vatives by substitution. Iodine combines directly with 
the molecule of strychnia. 

Strychnia dissolves in strong sulphuric acid; the so- 
lution is colorless and becomes dark blue in contact 
with potassium bichromate or lead dioxide. The 
color rapidly passes to red and finally to a yellow. 

Strychnia is colored yellow by hydrogen nitrate 
only when it contains brucia, a trace of which is suf- 
ficient to produce the change. 

Strychnia forms with acids crystallizable salts. 
The nitrate C2iH 2 2^N"202,HN0 3 crystallizes in fine 
needles very soluble in hot water. 

Strychnia is among the most powerful poisons, 2 to 
3 centigrams being sufficient to cause death. There is 
believed to be no reliable antidote for strychnia though 
F. M. Peirce claims that small doses of prussic acid 
are efficient for the purpose. (44-' 68-335.) 

brucia. 

CJ3JSfi to 4SJO. 

To obtain this alkaloid the alcoholic liquids from 
which strychnia has been removed, are saturated with 
oxalic acid and evaporated. The crystals of oxal- 
ate of brucia which are formed, are washed with 95 per 



162 ORGANIC CHEMISTRY. 

cent, alcohol and redissolved in water. The solution 
is decomposed by lime, the precipitate collected, dried 
and dissolved in boiling alcohol; brucia then crystal- 
lizes ont and is purified by two recrystallizations. 

Crystals of brucia are large and of the clinorhombic 
system; they are soluble in alcohol, insoluble in ether, 
but soluble in 850 parts of cold, or 500 parts of boil- 
ing water. 

Concentrated sulphuric acid strikes a rose color with 
brucia which afterwards changes to green. !N itric acid 
colors it red, and if heated it gives off nitrous ether, 
methyl alcohol and carbon dioxide. 

Brucia is much less poisonous than strychnia. 

It may be distinguished from strychnia by its reac- 
tion with nitric acid. A red color is produced by 
brucia, which passes to violet on the addition of 
stannous chloride. This latter coloration does 
not take place with morphia. Brucia is also one of the 
best reagents for nitric acid. 

Curaeina. — From the arrows of the Indians living 
on the shores of the Amazon and Orinoco, a brown 
resinous matter is collected, from which crystals of a 
substance have been obtained whose poisonous action 
is exceedingly rapid. Preyer, to whom we owe this 
discovery, regards its formula as C 10 H 15 N, and has 
named it curarina. 

The Indians of Dutch Guiana poison their arrows 
with two other substances no less dangerous: iirari 
and tihunas. These three substances paralyze the ac- 
tion of the muscles by destroying the motor nerves 



VEEATEIA. 163 

(Clande Bernard). It appears that urari, though a fa- 
tal poison when introduced into the blood by a wound, 
may yet be swallowed with impunity. 

DEASTIO POISONS. 

We shall not describe the preparation of the follow- 
ing alkaloids, on account of their minor importance. 
The process in general is similar to that by which the 
preceding ones are prepared: The alkaloid is dissolved 
in an inorganic acid, precipitated by a base, and redis- 
solved in an appropriate solvent. 

The roots of the white hellebore ( Veratrum album) 
and its seeds, furnish an alkaloid called veratria, 
C 32 H 52 N 2 8 . It crystallizes in prisms having a rhom- 
bic base. They are very bitter, insoluble in water, 
soluble in alcohol and ether, and melt at 115°. Vera- 
tria is dissolved by strong nitric acid, the solution be- 
ing violet. Sulphuric acid colors it first yellow, then 
red. 

Three other poisonous bases, sabadillia, colchinia, 
and jervia, are found associated with veratria in the 
Veratrum album. Jervia, C 20 H4 6 E" 2 O 3 2H 2 O, (Ger- 
hardt and Wills' analysis) is white, crystalline and 
fusible. 

These bodies are very corrosive poisons, producing 
great irritation of the alimentary canal. 

ALKALOIDS OF THE POISONOUS SOLANACE^E. 

The belladona, Atropa belladona* and the thorn- 
apple, Datura stramonium, furnish each an alkaloid 



164 ORGANIC CHEMISTRY. 

called, respectively, atropia and daturia, the formula 
of which is C 1T H 23 N0 3 . 

This substance crystallizes in fine needles, which are 
fusible at about 90°, and are partially sublimed at 
about 135°. It is difficultly soluble in water, but very 
soluble in alcohol and ether. 

Heated with an oxydizing agent, such as potassium 
bichromate, or sulphuric acid, it disengages essence of 
bitter almonds, easily recognizable by its odor, and 
crystals of benzoic acid are sublimed. With sulphuric 
acid a violet color is produced, accompanied by a fra- 
grant odor resembling that of a rose. 

Hydrochloric acid furnishes two acids with atropia, 
tropic C 9 H 10 O 3 , and atropia C 9 H 8 2 . 

Cases of poisoning by atropia are rare, but instances 
in which persons are poisoned by the berries of bella- 
dona are of frequent occurrence. 

The black henbane, Hyoscyamus niger, furnishes 
silky needles of a substance, hyoscia?nine, which has 
much resemblance to atropia, but whose action as a 
poison appears to be less violent. 

Its physiological action is on the nerves rather than 
on the muscles. It causes less dilation of the pupil of 
the eye, and produces a sombre delirium. 

Belladona and atropia, the datura, the henbane and 
hyosciamine, as well as the poisonous solanacese in 
general, should be classed among the narcotic poisons. 

Poisoning produced by belladona, and by most of 
the poisonous solanaceae, is characterized by great dila- 
tion of the pupils of the eyes. The patient is also 



ACONITINA. 165 

seized with vertigo and strange hallucinations followed 
by a turbulent delirium and convulsions. The face is 
congested, respiration difficult, and the skin often 
breaks out in an eruption similar to that in rubeola 
(measles). 

No antidote is known for these poisons; an infusion 
of unroasted coffee, tea, or other astringent substances 
is recommended, but the use of energetic emetics and 
purgatives is the most efficient method of treatment. 

The chemical characters of these alkaloids has not 
been as yet very fully studied. 

Desfosse has extracted from the woody nightshade, 
Solanum dulcamara, from the berries of the felon- 
wort and from the young sprouts of the potato, Sola- 
rium tube rosum, a substance called solanine, C 43 H n E"0 16 , 
a highly poisonous alkaloid. On being boiled with 
acids, it furnishes a stronger base solanidine and 
glucose. 

ACONITIKA. 

Aconitina is extracted from the monk's-hood, 
Aconitum napellus, as a colorless amorphous, bitter 
powder, soluble in alcohol, slightly soluble in ether, and 
almost insoluble in water. It fuses at 120°, and is al- 
kaline. It is a very active poison. Planta gives its 
formula as C 3 oH 47 ]N"O r ('(). 

Duquesnel has extracted from the Aconitum napel- 
lus a crystalline alkaloid, whose formula is G^H^KO. 



166 ORGANIC CHEMISTRY. 

DIGITALIN. 

•This substance was long ago obtained in an amor- 
phous condition from the purple fox-glove. In 1871 
Nativelle succeeded in obtaining it in a crystalline 
form. An extract of fox-glove is first prepared, con- 
centrated by distillation and dilluted with 3 times its 
volume of water. 

A precipitate is formed which contains two bodies, 
digitalin and digitin. This deposit, washed with 
boiling alcohol, furnishes crystals composed of these 
two substances, which are easily separated by chloro- 
form, as digitalin is dissolved by it in all proportions, 
while digitin is insoluble. 

The proportion of digitalin in Digitalis grown in 
different countries, has been made the subject of 
special investigation by Prof. S. P. Duffield, of 
Detroit. (94-1868.) 

Digitalin is very bitter to the taste. It powerfully 
irritates the nostrils, and is an active poison. If digi- 
talin be moistened with strong sulphuric acid and then 
exposed to the vapors of bromine, it assumes a purple 
color, which is darker or lighter according to the pro- 
portions employed. Hydrochloric acid produces with 
digitalin a very intense emerald green color. 

One-fourth of a milligram is sufficient to produce 
the ordinary poisonous effects ot digitalis. A milli- 
gram produces, in from three to five days, a marked 
change in the circulation. Three milligrams produce 
most dangerous effects within 24 hours. 



EMETIA. 167 

It is much to be desired that physicians substitute 
this crystalline substance, which is invariable, for the 
amorphous digitalin, which varies greatly, both as to 
character and effectiveness. Tardieu places digitalin 
among the hyposthenic poisons. 

Poisoning by digitalin has often been produced 
through imprudence. 

The upas antiar, with which the Indians poison 
their arrows, is obtained from the Antiar is toxicaria. 

EMETIA. 

This body is obtained from the roots of the ipecac- 
uanha, Cephoelis ipecacuanha; it also exists in the 
Ricliardsonia braziliensis, in the Phsychtria emetica, 
and in the roots of the Cainca (madder tribe). These 
materials, reduced to a powder, are treated with con- 
centrated alcohol, and the alcohol then distilled off. 
The extract is diluted with five times its volume of 
water, and filtered. To the filtrate 2 per cent, of 
caustic potassa is added, and this mixture agitated 
with chloroform. The chloroform is decanted and 
distilled ; the emetia crystallizes out. It is dissolved 
in dilute sulphuric acid, and precipitated from the so- 
lution with ammonia. A. G-lenward (105-[3] 6 — 201) 
gives C^H^NO^ as the formula of emetia. 

It is amorphous, yellowish, fusible at 50°, soluble 
in water and alcohol. Its solutions are slightly bitter. 
It is a very weak base, and its salts are not crystalline. 
A few centigrams suffice to produce vomiting. 



168 ORGANIC CHEMISTRY. 

CANTHARIDIN 

is a very poisonous crystalline substance, obtained from 
Spanish flies, (Lytta vesicatoria, and other varieties) 
and has the composition C 3 H 6 2 . It is present in 
nearly all parts of the flies, varying in amount from 0.5 
to 1.2 per cent. R. Wolff has of late given this sub- 
stance a very full investigation. (95, May, '77-102.) 

CAFFEINE (CAFFEIA) OR THEIXE (THEIA). 

C 8 H 10 N 4 O 2 ,H 2 O. 

Alcohol is added to a mixture of 5 parts coffee and 
1 part slacked lime, until nothing further is dissolved, 
and the solution distilled. The residue is treated 
with water, which causes an oil to separate out. 
The watery liquid furnishes crystals which are puri- 
fied by treating with animal charcoal, and recrystal- 
lizing in hot water. 

The extractive matters of the Jcolarnut aii&mate pos- 
sess the same properties as caffeine. 

Caffeine crystallizes in fine needles, fusible at 178°, 
and is volatile at a slightly higher temperature. These 
crystals are but little soluble in ether and cold water, 
yet dissolve very readily in alcohol and boiling water. 

It is remarkable that the instinct of man should 
have led him to select, as the bases of common bever- 
ages, just the four or five plants, which out of many 
thousands are the only ones, as far as we know, con-, 
taining caffeine. 



THEOBROMINE. 169 

It is recognized by boiling with fuming nitric acid ; a 
yellow liquid is produced. On being evaporated to 
dryness, and ammonia added to the residue, a purple 
coloration is produced, resembling murexide. (p. 125.) 
Amalic acid and Oholestrophan are products of the 
action of oxidizing agents upon caffeine; bodies link- 
ing this alkaloid to the uric acid group. 

THEOBROMINE. 

There is extracted from the caco, Theobroma cacao, a 
principle crystallizing in microscopic crystals, volatile 
at 295°, soluble in alcohol and ether, and slightly so in 
water. It furnishes salts which are decomposed by 
water. It is called theobromine ; its formula is C 7 H 8 

PICROTOXIN. 

C 5 H 6 2 . 

From the Indian berry, Cocculus Indicus, there is 
extracted a white crystalline matter of extreme bitter- 
ness, called picrotoxm r (from 7riKpo5 bitter ro^ixov.) 
This body is neutral, difficultly soluble in water, and 
easily soluble in alcohol and ether; its solutions are 
levogyrate. 

The physiological action of picrotoxin is analo- 
gous to that of strychnia, but it differs from it in that 
it renders the action of the heart slower, and produces 
vomiting. 

Prof. J. W. Langley, of Pittsburg, has contributed 



170 ORGANIC CHEMISTRY. 

much to (87-1862) our knowledge of the chemical 
character of picrotoxin. 

POLYATOMIC ALKALOIDS. 

There are polyatomic bases which are to the mona- 
tomic bases what polyatomic alcohols are to monatomic 
alcohols. 

They are built upon the type of several molecules 
of ammonia, or condensed ammonia, in the same man- 
ner that polyatomic acids and alcohols are derived 
from several molecules of water. 

Cloez obtained the former by the action of ethylene 
bromide upon potassa dissolved in alcohol. 

Hoffmann established their true formula. They are 
called poly amines. 

EXAMPLE. 

Ethylenic diamine. N 
Diethylenic " 

Triethylenic " 

tjeea. 

(CO" 

CH 4 ¥ 2 0=N 2 H 2 




H 



POLYATOMIC ALKALOIDS. 171 

itouelle, Jr., was the first to obtain this body in an 
impure state from urine. 

Fourcroy and Vanquelin first obtained it pure. 

"Woehler, in 1828, prepared it artificially by a remark- 
able synthesis, the first attempt to form a body syn- 
thetically. Urea forms the chief constituent of the 
urine of mammalia, amounting to nearly one-half of the 
solid constituent; a small proportion of urea is found 
in all the fluids of the body. 

It is an excretory product, as the hydrogen and 
carbon which have taken their part in the body, escape 
mainly in the form of water and carbon dioxide, so 
the nitrogen is eliminated from the system chiefly in 
the form of urea. 

Urea may be extracted from urine by evaporating 
this liquid to one-tenth its volume and adding, after it 
has become cold, an excess of nitric acid. Brown 
crystals of nitrate of urea are formed: these are drain- 
ed, expressed, re-dissolved in water and boiled with 
animal charcoal. This solution is filtered, and on 
evaporation it deposits crystals of nitrate of urea. 
This salt is then dissolved in as small a quantity of 
water as possible, and the solution treated first with 
barium carbonate, then with a strong solution of potas- 
sium carbonate; urea is set free and barium and potas- 
sium nitrates formed. The above mentioned salts are 
added as long as effervescence is produced; the liquid 
is then evaporated to dryness, and the residue treated 
with absolute alcohol, which dissolves only the urea. 
(J. E. Loughlin, 100-5-362.) 



172 ORGANIC CHEMISTRY. 

The synthetic method employed by Woehler, con- 
sists in preparing cyanate of ammonia, which body is 
isomeric with urea. 

Cyanate of Ammonitjm=H 4 CN' 2 0=NH4-"0-CK 

This substance changes spontaneously into urea. 

Heat, upon an earthen plate,' 28 parts of potassium 
ferrocyanide and 14 parts of manganese dioxide, both 
finely pulverized, and dry until the mixture becomes 
pasty; when cold, the mass is pulverized and treated 
with water, and 20 parts of ammonium sulphide added 
to the liquid, which is now evaporated in a water bath, 
and the residue treated with boiling alcohol. On 
evaporating the alcoholic solution, crystals of urea are 
deposited. Urea is also obtained as a product of other 
reactions. It crystallizes in prisms of the tetragonal 
system; these crystals are colorless, without odor, and 
have a cooling taste. 

It is soluble in its own weight of water at 15°, in an 
equal weight of boiling alcohol, and in 5 parts of cold 
80 per cent, alcohol ; it is difficultly soluble in ether. 
Its solutions are neutral. 

Urea fuses at 120°; at about 150° it is decomposed, 
yielding ammonium carbonate, ammelide, C 3 OH 5 N 5 , 
and biuret, C^0 2 ^-^^ 

Oxydizing agents decompose urea. Chlorine also 
decomposes solutions of urea in the following man- 
ner : 

3Cl 8 + H a O + CH 4 N 2 0=6HCH-N 8 + CO a . 

Urea heated to 140° with water in sealed tubes, is 
transformed into ammonia and carbon dioxide: 



UEEA. 173 

H 2 + CH 4 N 2 0=C0 2 + 2NH 3 . 

This transformation likewise occurs when urea is 
heated with strong sulphuric acid, or fused with po- 
tassa, also, spontaneously, in presence of the nitro- 
genous matters of the urine. 

Urea does not appear to unite with all acids. It has 
not yet been combined with carbonic, chloric, lactic or 
uric acids. The nitrate, chloride and oxalate of urea 
are crystalline. 

Urea forms combinations with mercury, silver, 
and sodium oxides, also with mercuric and silver 
nitrates, etc. 



174 ORGANIC CHEMISTRY. 



NATURAL FATS AND OILS. 

The fatty bodies are very widely distributed through- 
out the vegetable and animal kingdoms. Some are 
liquid, others are more or less solid. Certain oils re- 
main liquid exposed to the air, as olive oil; others 
oxydize and thicken, as linseed oil, poppy oil, and 
nut oils; the latter are called siccative oils, and are 
used in the manufacture of varnishes, printers' ink, 
oil cloth, also in paints. 

Fats and oils are insoluble in water; they are among 
the very few bodies which are wholly insoluble in 
this menstrum; they are also, in general, difficultly 
soluble in alcohol. They generally dissolve in ether, 
and the liquid hydro-carbons. Their specific gravity 
is less than that of water. 

Heat destroys them ; acrolein is usually formed 
associated with other products. 

Since oil and water repel each other, many other 
substances may be protected from moisture by simply 
coating them with oil. Shoe-leather may be rendered 
water-proof and iron protected from rusting by greas- 
ing. Wood, saturated with oil, will last for a long 
time when buried in moist ground. 

Stearin" or Stearine, (from (xrsap, suet) C 5T H 110 O 6 , 
is prepared by melting suet in turpentine; the two 
other proximate principles present, are precipitated, 



FATS AND OILS. 175 

while the stearin e remains in solntion. It is separated 
from the liquid by water, and purified by several re- 
crystallizations in ether ; it fuses at 71°, and solidifies 
at^O . 

Berthelot has reproduced stearine synthetically, by 
heating 3 parts of stearic acid with one part of glyc- 
erine, in a sealed tube. 

This synthesis, as well as other researches, estab- 
lishes the fact that the neutral fats are compound 
ethers of glyceryl, and the fatty acids. 

On account of the heat generated by oxidizable 
oils when exposed to the air, frequent instances of 
spontaneous combustion occur when cotton rags, or 
waste soaked with oil, are allowed to remain in a heap. 

Fats, especially if mixed with nitrogenous matter, 
become acid, rancid. The chemical nature of this 
change is not entirely understood. 

Olein or oleine, is the chief constituent of olive oil 
and fish oil. Berthelot has shown, by the action of 
oleic acid on glycerine, that natural oleine is a mix- 
ture of monokine, dioleine, and trioleine. Oleine 
heated with a small quantity of mercury nitrate, or 
any other body capable of furnishing nitric oxide, be- 
comes solid, owing to the transformation of the oleine 
into an isomeric body, elaidine. Siccative oils contain, 
instead of oleine, another principle called elaine. 

Neutral fatty bodies and other ethers of glycerine 
are decomposed by alkaline solutions ; a combination 
with water takes place, glycerine and fatty acids are 
formed. We may take as an example, stearin. 



176 OEGrAJSTIC CHEMISTRY. 

3KHO+0 n H 1M O 6 =3(Z0 18 H 8B O 2 )+C»H fl O8. 

Alkalies, therefore, react upon the ethers of glycerine 
in the same manner as do the ethers of glycol and 
ordinary alcohol. This reaction is called saponifica- 
tion, and soaps are salts formed by stearic, margaric, 
and oleic acids, with a metal. 

SOAPS. STEAKIXE CANDLES. 

The only soluble soaps are those whose base is 
potassa or soda. Soda soaps, those ordinarily in use, 
are hard, while potassa soaps are soft. On adding to 
an aqueous solution of soap a solution of a metal, a 
precipitate is formed which is the soap of the metal 
employed ; thus the precipitate which common water 
produces in soap is a lime soap. 

Ordinary soap is made by boiling fats of inferior 
quality with an alkaline solution. When the oil is 
completely decomposed the soap is precipitated by 
salt water, in which soap is insoluble. 

Stearine candles have hitherto been made by saponi- 
fying suet or tallow with lime in the presence of boiling 
water. At present the amount of lime employed in 
the saponification is considerably diminished (amount- 
ing to only 4 per cent.) by operating at a temperature 
of 150°. 

The saponification of fats of inferior quality is also 
effected by means of sulphuric acid instead of lime; 
this acid forms with the fatty acids, double or conju- 



FATS AND OILS. 177 

gate acids, which are decomposed by water. The de- 
composition of fats into their constituents, the fatty 
acids and glycerine, for the manufacture of candles, is 
at present effected on a large scale by simply heating 
the fats with steam under pressure, and at a tempera- 
ture of 260°. This is the celebrated process of the 
American inventor, Tilghman, to whom the wonder- 
ful " sand blast " is also due. 

This decomposition of fats is most remarkable, as, 
by the same process, only at a lower temperature, 
Berthelot obtained a result exactly the reverse, caus- 
ing stearic acid and glycerine to reform stearine by 
simple direct synthesis. 

Stearic acid, C 18 H 36 2 , is crystalline, insoluble in 
water, soluble in alcohol and ether, and melts at 70°. 
It unites with the bases ; its alkaline salts alone are 
soluble. 

Margaric acid, having the formula C^H^C^, (from 
jxapyapov, a pearl, owing to its pearly lustre) is crys- 
talline. It melts at 60° and forms salts with the metals. 

Oleic acid, C^H^O-^ is an oil becoming colored in 
the air and converted into an acid called elaidic acid,, 
which is fusible at 44°, in contact with a small quantity 
of hyponitric acid. 

These three acids, stearic, margaric, and oleic, are 
those that, with glycerine, constitute most of the natu- 
ral fats, or glyceryl ethers. 

Lead plaster is essentially a lead-soap compound 
of plumbic oleate. 



178 ORGANIC CHEMISTRY. 

CEOTON OIL. 

This oil is extracted from the seed of the Croton 
tiglium of the family of euphorbiaceaB. 

The seeds are ground and expressed, or they are 
treated with ether, which is afterwards driven off by 
distillation. 

This oil is yellowish, very bitter, and possesses a 
disagreeable odor. Alcohol and ether dissolve it. It 
produces blisters whenever it comes in contact with 
the skin, and is a drastic poison. 

Pelletier and Caventou have extracted from this oil 
an acid body, C 4 H 6 2 , denominated crotonic acid. 

COD-LIYEE OIL. 

This oil is extracted from the liver of the cod, and 
several other species of the genus Gadus. Two pro- 
cesses are employed for its extraction ; either the oil 
is obtained by putrefaction, in which case the oil 
separates out naturally, or the livers are cut into small 
pieces and heated in large pans, then placed in cloth 
sacks and pressed. It is of a brownish color. A white 
oil is sometimes sold, which has been bleached by 
treatment with weak lye and animal charcoal. The 
efficiency of this latter oil is much less than that of 
the natural oil. 

There has been found in this oil 3 to 4 thousandths 
of iodine, and a small quantity of phosphorous ; and 
its medical qualities are thought to be due to these 



wax. 179 

two substances, but it is probable that its efficiency is 
more frequently due simply to its fatty character. 

BUTTEB. 

Ordinary Butter. Butter contains stearic, mar- 
garic, oleic, and butyric acids, and several other 
proximate neutral principles. Its density is 0.82. It 
dissolves in 30 per cent, of boiling common alcohol. 
The odor which it emits on becoming rancid is due to 
the liberation of fatty acids. 

" Oleo -margarine" is artificial butter, consisting 
mainly of oleine and margarine obtained from suet or 
lard. 

SPEBMACETI. 

This substance which is formed in peculiar cavities 
in the head of the sperm whale, and is a neutral 
fatty body sometimes employed in pharmacy. It is 
an ether, which, on saponification, produces a fatty acid 
called ethalio acid, and a monatomic alcohol, ethal. 

H,O+0»H«O,=C„H„OHO + OAO 



Spermaceti. Ethalic Acid. Ethal. 

WAX. 



Yellow bees-wax is obtained by submitting honey- 
comb to pressure, then fusing the same under boiling 
water. It is bleached by being cut into thin cakes 
and exposed to the air and sunlight. Thus prepared 



180 ORGANIC, CHEMISTRY. 

it fuses at 62°. Mixed with. 3 per cent, of oil of 
sweet almonds it forms a cerate, used in pharmacy. 

On being treated with alcohol it separates into two 
proximate principles: one, soluble in this liquid, is 
acid, and is called cerotic acid, having the formula 
C27H54O; the other, which is but slightly soluble, is 
called myricin. The latter is a compound ether, 
and is decomposed by bases into an acid, ethalic acid, 
and an alcohol, melissic alcohol, C^H^O. 

CASTOR OIL. 

This oil is extracted from the Ricinus communis, a 
plant of the family of Euphorbiacese. 

The castor-oil beans are hulled, pulverized, and 
the pasty mass obtained subjected to strong pressure. 
This oil is slightly yellow. Its density is 0.926 at 
12°, and it remains liquid at a temperature of —18°. 
It is very soluble in alcohol, a characteristic which 
distinguishes it from most other oils. 

This oil is also an ether of glycerine; the acid which 
it contains is ricinoleic acid, C^H^C^. 



SUGARS. 181 



STTGAKS. 

The general name of sugars, by some regarded as 
polyatomic alcohols, is given to bodies which are capa- 
ble of fermenting, that is, of decomposing directly or 
indirectly into different products, of which the princi- 
pal ones are alcohol and carbon dioxide. Fermenta- 
tion requires the presence of certain microscopic 
plants, and, according to Pasteur, is a phenomenon 
correlative with the vital development of these 
organisms. This, however, has been latterly dis- 
proved by Tyndall. 

Sugars may be divided into three classes. In the 
first are those in which the proportion of hydrogen 
is more than sufficient to convert the whole of the oxy- 
gen into water. It contains : 

Mannite, C 6 H 14 6 , extracted from manna. 

Dulcite or melampyrite, C 6 H 14 6 , found in Mada- 
gascar. 

Pinite, C 6 H 12 5 , extracted from a Californian pine 
tree. 

Quercite, C 6 H 12 5 , extracted from acorns. 

These bodies do not ferment with beer yeast alone; 
but in presence of certain ferments and calcium car- 
bonate they furnish alcohol, carbon dioxide, and hy- 
drogen. 

Sugars of the second and third class contain hydro- 
gen and oxygen in the proportions to form water. 



182 OKGANIC CHEMISTRY. 

The second class includes the glucoses, isomeric 
bodies, whose general formula is, C 6 H 12 6 . Among 
these are: 

Ordinary Glucose or grape sugar. 

Zevulose, associated with glucose in the form of 
inverted sugar. 

Maltose, obtained from malt. 

Galactose, obtained by treating sugar of milk, or 
gums, with dilute acids. 

Eucalin, obtained by the action of maltose on beer 
yeast. 

Sorbin exists in the berries of the mountain ash. 

Inosite is found in the embryo of young plants 
and in the fluids of flesh. 

Lactose or Sugar of Milk. The glucoses may be 
divided into two series. The first includes those bodies 
(ordinary glucose, levulose) which, on being oxydized, 
form saccharic acid, and on being hydrogen ized by 
means of sodium amalgam, produce mannite. The 
second includes those substances (galactose, lactose) 
which, on oxydation produce mucic acid, and on hydro- 
genation furnish dulcite. The third class of su- 
gars contains bodies whose general formula is C^H^On, 
and are called saccharoses, by Berthelot. It contains, 
besides cane sugar, three bodies called: 

Mditose, an exudation of certain eucalypti. 

Trehalose or mycose^ extracted from the Turkish 
manna and certain mushrooms. 

Melezitose, obtained from an exudation of the larch. 

The sugars of the first two classes are placed by 
Berthelot among the polyatomic alcohols. 



MANNITE. 183 

MANNITE. 

C 6 H 14 6 . 

This body exists naturally in an exudation of vari- 
ous species of ash {Fraxinus rotundifolia), called 
manna, of which it forms the greater portion. It is 
also found in mushrooms, algae, the sap of most fruit 
trees, onions, asparagus, celery, etc. It may be pre- 
pared by dissolving manna in one-half its weight of 
water, to which a small quantity of egg albumen is 
added, and the mixture brought to boiling and filtered. 
On cooling, colored ciystals are deposited which are 
expressed and redissolved in hot water. This solution 
is mixed with animal charcoal, boiled and filtered while 
hot. The liquid deposits crystals on cooling. Man- 
nite crystallizes in rhombic prisms and has a sweet taste. 
It dissolves in seven times its own weight of cold wa- 
ter, is slightly soluble in alcohol, and insoluble in ether. 
Its solutions are optically inactive. 

Mannite fuses at about 165°; at about 200° it yields 
a certain quantity of a substance called Mannitane, 
C 6 H 12 5 . It oxydizes in presence of platinum black, 
furnishing a non-cry stallizable acid called mannitic 
acid. Boiling nitric acid converts it into saccharic 
and oxalic acids. 

Mannite, treated with a small quantity of nitric acid, 
is changed into a body insoluble in water, called 

nitro-mannite, \-*fr\ V [ 6 , which may be regarded 
as a compound ether. 

Dulcite. — Dulcite is very analogous to mannite, but 
differs from it, in that it furnishes, with nitric acid, 
mucic acid. 



184 ORGANIC CHEMISTRY. 



GLUCOSES. 
C 6 H 12 6 . 

These compounds may be considered as representa- 
tive carbohydrates. Ordinary glucose (from yXvjivS, 
sweet,) or grape sugar, is a crystalline substance, and is 
found in honey, figs, and various other fruits, together 
with another insoluble glucose. It has been found in 
small quantity in the liver and in most of the fluids 
of the body. It is obtained by the decomposition of 
salicine, tannin, and other substances, which, for this 
reason, have been named glucosides. 

Vegetable cellulose, the envelope of many inverte- 
brates (chitin and tunicin) and the glycogenous princi- 
ple of the liver furnish glucose on treatment with 
dilute acids. 

It is manufactured on a large scale by the action of 
starch upon dilute sulphuric acid. Water containing 
four to eight per cent, of sulphuric acid is placed in 
vats and heated to boiling by means of superheated 
steam. Before the water boils, starch mixed with 
water is added, and ebullition maintained as long as a 
small quantity of the mixture gives a blue reaction 
with iodine. The sulphuric acid is not changed during 
this transformation. 

It is then saturated with chalk and the liquid allowed 
to become clear. It is decolored by passing through 



GLUCOSES. 185 

filters containing animal charcoal and evaporated to a 
density of 41° Baume. The glucose crystallizes in 
compact masses. Often the liquid is evaporated to 
only 3° B., when a syrup is obtained known as starch 
syrup. Honey treated with cold concentrated alcohol, 
also furnishes glucose. The crystals of glucose are 
small, opaque, and ill defined. 

They are represented by the formula C 6 H 12 6 ,2H 2 0, 
but they may be obtained having the composition 
C 6 H 12 6 by precipitating the glucose in boiling concen- 
trated alcohol. The water may also be driven off by 
heating the glucose to about 100°. 

Glucose is soluble in a little more than its own 
weight of water. Weak alcohol dissolves it readily. 
It is slightly soluble in cold concentrated alcohol. 

Its solutions turn the plane of polarization to the 
right. This rotatory power is feeble in the cold. 

Glucose, heated to about 170°, acts in the same man- 
ner as mannite. Gelis has demonstrated that it loses 
a molecule of water; the body formed C 6 H 10 O 5 , is 
called glucosane, C 6 H 12 Q 6 =C 6 H 10 O 5 + H 2 O. It re- 
produces glucose on being boiled with acidulated 
water. If glucose is boiled with dilute nitric acid, 
saccharic and oxalic acids are formed. Fuming nitric 
acid forms with glucose a very explosive compound. 

Hydrochloric acid turns it brown. With dilute sul- 
phuric acid it furnishes a double acid (sulphogrlucic 
acid)\ with strong sulphuric acid, carbon. Glucose 
oxydized with care, furnishes saccharic acid. 

Heated to 100° with butyric, or various other acids, 



186 ORGANIC CHEMISTRY. 

it loses water, and the glucosane formed reacts upon 
the acid, forming an ether, saccharide, or dibutyric 
glucosane, 



(C 6 H 6 ) 
(C 4 H 7 0)H 



<X 



This body, as well as other saccharides, are decom- 
posed under the action of boiling acidulated water, 
into an acid and glucose. 

Glucose combines, with sodium chloride, forming 
several crystalline compounds; it also forms unstable 
compounds with the metallic bases, 

CaC 6 H 10 O 6 
BaC 6 H u 6 , etc. 

Peligot has shown that the solutions of these glucos- 
ates are gradually changed into salts of a special acid 
called glucic acid, whose formula is 

Ci2S 18 9 . 

Cupric acetate boiled with glucose is reduced to the 
state of suboxide. 

This action, which is very slow with salts of copper 
with inorganic acids, becomes rapid and complete in 
presence of alkalies. On adding glucose to a solution 
of copper sulphate, this salt is not precipitated by 
potassa. If, however, the liquid is heated, it deposits 
cuprous oxide. (Trommer's test.) This reaction is 
more delicate with copper salts, whose acids are 



GALACTOSE. 187 

organic. A mixture is used of copper sulphate, 
Kochelle salt and soda (Fehling), or a solution of 
copper tartrate in potassic hydrate. (Barreswil.) 

Prof. W. S. Haines has found in glycerine a very 
desirable substitute for the tartrate in Fehling' s test. 
The proportions employed by him for qualitative ex- 
aminations are: cupric sulphate, 30 grains; potassic 
hydrate, li drachms; pure glycerine, 2 fluid drachms; 
distilled water, 6 ounces. 

LEVTTLOSE, C 6 H 12 6 . 

This name is given to a variety of glucose, which is 
found in many fruits. It may be obtained by boil- 
ing inulin with water, or, better, it can be prepared 
from cane sugar by the action of dilute acids. It 
differs from the other sugars in that its rotary power 
diminishes on heating. 

GALACTOSE, 

C 6 H 12 6 . 

This body is produced by boiling, for two or three 
hours, sugar of milk with water acidulated with 
sulphuric acid. It is soluble in water and insoluble in 
alcohol; nitric acid transforms it into mucic acid. 

LNOSLN, INOSLTE OR MUSCLE SUGAR. 

C 6 H 12 6 + 2H 2 0. 
This substance is found in many animal organs, and 



188 ORGANIC CHEMISTRY. 

is the chief constituent of the liquid which impreg- 
nates the muscles. 

It may be prepared by first extracting the creatin 
from the muscles, then separating the inosic acid with 
baryta. To the liquid is then added a quantity of 
sulphuric acid sufficient to precipitate the whole of the 
baryta and the liquid treated with ether, which dis- 
solves the foreign substances. 

The aqueous solution is removed and alcohol added 
to it until a precipitate is formed. Crystals of potas- 
sium sulphate first separate out, then beautiful crystals 
of inosite. This substance has a sweet taste. At a 
temperature of 100° it loses two molecules of water. 
It dissolves in one-sixth of its weight of water while it 
is insoluble in ether and strong alcohol. 

Inosite is without action upon polarized light. It 
is not converted into glucose by the action of dilute 
acids, and does not reduce copper salts. Mixed with 
milk and chalk it undergoes lactic fermentation. 
(Page 122.) 



SACCHAROSES. 189 



SACCHAEOSES. 
Ordinary Sugar, 

This body exists in a large number of plants, 
though it is almost exclusively extracted from the 
sugar-cane and beet-root. 

The sugar-cane, Arundo saccharifera, contains 17 
to 20 per cent, of sugar. To extract, the juice of the 
cane is first obtained by expressing. This juice repre- 
sents 60 to 65 per cent, of the total weight of the cane, 
and would alter rapidly in the air if care were not 
taken to bring it rapidly to a temperature of 70°, and 
adding a quantity of lime. The juice soon becomes 
covered with foam and deposits different albuminoid 
and other matters, which are precipitated by the lime. 
It is decanted into pans and rapidly evaporated. The 
sugar crystallizes out, and the mother liquor is evapo- 
rated as long as it furnishes crystals. The thick liquid 
which remains is molasses. The sugar thus obtained 
is brown sugar, and is subsequently refined. 

The beet-root most rich in sugar is that of Silesia. 
It contains about 10 per cent, of sugar. Sugar crys- 
tallizes in clinorhombic prisms. They may be readily 
obtained by slowly evaporating a solution of sugar. 



190 ORGANIC CHEMISTRY. 

The crystals of ordinary sugar are very small, as the 
syrup is made to crystallize quite rapidly. Cold water 
dissolves three times its weight of sugar; hot water 
dissolves it in all proportions, forming a syrupy liquid. 
It is not dissolved by cold alcohol or ether. Dilute 
alcohol dissolves it in proportion as it is more or less 
aqueous. Its solutions are dextrogyrate. Sugar melts 
at about 180°, and yields a liquid which solidifies 
to a vitreous, amorphous mass, called barley sugar, 
which becomes opaque and crystalline after some time. 

If sugar is heated a little above this point, it is 
transformed into glucose and levulosane. 

Ci 2 H 22 On=C 6 II 12 6 4- C 6 H 10 O 5 . 

Levulosane. 

At about 190° sugar loses water, becomes brown, 
and finally furnishes a substance which is commonly 
known as caramel. According to G-elis three pro- 
ducts of dehydration are formed, caramelane, cara- 
melene and carameline. At a tempsrature of 230° 
to 250° sugar is decomposed into carbon monoxide, 
carbon dioxide, carbohydrides and different empyreu- 
matic products. Sugar is transformed slowly in the 
cold, and rapidly at 80°, in contact with dilute acids 
into inverted sugar, which is thus called on account 
of its inverted action upon polarized light. On pro- 
longed ebullition the solution is rendered brown and 
ulmic products are formed. Sugar reacts with baryta 
water and lime water, forming different compounds 
called sucrates or saccharates. 



SUGAR OF MILK. 191 

The solutions of these sucrates are decomposed by 
carbon dioxide : sugar is reformed. Rousseau makes 
use of this fact in the manufacture of sugar on a very 
large scale. 

Sugar does not ferment immediately in contact 
with beer yeast. 

SUGAR OF MILK, LACTIN OR LACTOSE. 

C 12 H 22 O n + H 2 0. 

It is obtained from milk, by precipitating the casein 
with a few drops of dilute sulphuric acid, filtering 
and evaporating the liquid. 

Crystals are deposited, which are purified by re- 
dissolving and treating with animal charcoal. 

In Switzerland large quantities of sugar of milk 
are made by evaporating the whey which remains 
after the separation of the cheese. 

The crystals of this body are rhombic prisms. 
This sugar is insoluble in ether and alcohol, and 
requires 2 parts of boiling and 6 parts of cold water 
for its solution. 

Its solutions are dextrogyrate. At a temperature 
of about 140° it loses H 2 0, and becomes brown at 160° 
to 180°. 

In presence of sour milk and chalk it undergoes 
lactic fermentation. 

Sugar has been found in a sample of a saccharine 
matter extracted from the sap of a sapodilla tree, the 
tree furnishing caoutchouc. 



192 ORGANIC CHEMISTRY. 

Reichardt has obtained from gum arabic a sugar 
distinct from ordinary sugar, a body though having 
the same formula. He names it jpara-ardbin. 

HONEY. 

Honey is produced by the domestic bee (Apis mel- 
lifica), an insect of the order Hymenoptera. 

It is separated from the wax by exposing the honey- 
comb to the sun, on wire nets ; very pure honey is 
thus obtained. 

The mass which remains is expressed, and this prod- 
uct is a second quality of honey, more colored and 
of a less agreeable taste and odor than the first. The 
comb is then heated with water to remove the remain- 
der of the honey. The wax thus isolated is melted 
and run into moulds. Honey owes its sweet taste to 
several sugars. There is found in it a dextroyrgate, 
crystallizable glucose, and on removing this sugar 
there remains a viscid uncrystallizable liquid, which 
contains levnlose. In addition to these, small ouan- 
tities of ordinary sugar have also been found in 
honey. 

GLTTCOSIDES. 

This name is given to certain bodies which have 
the property of forming various products by combin- 
ing with water, among which is glucose, or some other 
saccharine matter. 

This change is produced by the action of acids, 
bases, or by the action of ferments. We cite the fol- 
lowing, but shall only study the most important: 



GLTTCOSIDES. 193 

Salicin, C 13 H 18 7 , extracted from the bark of the 

Willow. 

Amjgdalin, C^H^NOn, extracted from the Bitter 
Almond, Amygdalus communis. 

Orcin, C 7 H 8 2 , extracted from various Lichens. 

Tannin, C 27 H 22 17 , extracted from the Oak. 

Phlorizin, C^H^Oxo, extracted from the Apple, Pear, 
or Cherry tree. 

Populin, C 20 H 22 O 8 , extracted from Aspen leaves. 

Arbutin, C 13 H 16 7 , extracted from the leaves of the 
Uva-Ursa. 

Convolvulin, C 31 H 30 O 16 , extracted from the Convol- 
vulus orizabensis and schiedeanus. 

Jalappin, C^HgeO^, extracted from Convolvulus 
orizabensis and scammonia. 

Saponin, a white amorphous powder whose solution 
is very frothy and of which the powder is very sternu- 
tatory. 

Daphnin, CsolI^Oig, the crystalline matter extracted 
from the bark of the Ash {Fraxinus excelsior). 

Cyclamin ^H^O^, extracted from the tubercles of 
the Cyclamen eurojXJeum. 

Quinovin, C^li^Os, a resinous, bitter matter, solu- 
ble in alcohol, existing in the bark of the Quina nova 
and other cinchonas. 

Solanin, C^H^NO^. This has already been studied, 
(page 165). 

Esculin, CgoH^Ojg, extracted from the bark of the 
Horse Chestnut. 

Qnercitrin, C 29 H 30 O 17 , from the bark of the yellow 
oak (Quercus tinctoria). 



194 ORGANIC CHEMISTRY. 

Coniferin, C 16 H 22 8 , from the Larix europaea, etc. 
Vanillin, from the Vanilla bean, and recently ob- 
tained artificially (60-74-608). 

SALICIN, C 13 H 18 07 + H 2 0. 

This body crystallizes in white needles, fusible at 
120°, insoluble in ether, soluble in alcohol and water. 
These solutions are levogyrate and very bitter. It is 
used as a febrifuge, bnt is of little value in well de- 
fined intermittent fevers. 

It has as a distinguishing chemical character, the 
property of becoming red with sulphuric acid. 

Under the action of dilute sulphuric, or hydro- 
chloric acid, or even with emulsin, salicin is decom- 
posed. With the latter the reaction is: 

C 13 H I8 0, + H,0 =C,H B 0, + C 7 H A 

Glucose. Saligenin. 

In contact with cold nitric acid it loses hydrogen, 
and a body is formed called helicin, C 13 H 16 7 . 

"When treated with oxydizing agents, it gives off an 
odor which is identical with that of the essence of 
meadow sweet (Spirea ulmaria). 

This body is produced especially when salicin is 
treated with a mixture of sulphuric acid and potas- 
sium bichromate, and is also known by the name of 
hydride ofsalicyl. 

Its formula is identical with that of benzoic acid, 
C 7 H 6 2 , but it has not the properties of this acid. 



SALICIN. 195 

It is an aromatic liquid, boiling at 196°, and has the 
property of oxydizing spontaneously, giving rise to 
an acid called salicylic acid, C 7 H 6 3 . 

Saiicin, treated with fused potassa, furnishes potas- 
sium oxalate and salicylate. Cahours has shown that 
essence of Gaultheria procumhens, a heath of New 
Jersey, contains, besides, an isomer of the essence 
of turpentine, a sweet-scented liquid, boiling at 220°, 
which is salicylic methyl ether, and is re-converted, 
in contact with alkalies, into methyl alcohol and sali- 
cylic acid : it may be produced artificially by treating 
wood spirit with a mixture of salicylic and sulphuric 
acids. 

Salicylic or oxyhenzoic acid has been lately pro- 
duced by Kolbe (56 -'74 -22), by a remarkable syn- 
thesis in acting on carbolate of sodium with C0 2 . 

2C 6 H 5 ONa + C0 2 =C 6 H 6 + C 7 H 4 3 :Na 2 . 



Sodium phenol. Sodium salicylate of sodium. 

It has now come to be a very important article in 
pharmacy and in the arts, on account of its efficiency 
as an antiseptic, equaling or surpassing carbolic acid 
(phenol), yet without the unpleasant odor of the latter 
body, or its toxical qualities. As of considerable im- 
portance theoretically, it should be stated that Herr- 
mann has very lately (60- April, '77) obtained salicylic 
acid by the action of sodium upon succinic ether. 



196 ORGANIC CHEMISTEY. 



tannins. 

This is the name given to different principles exist- 
ing in plants, which are characterized by the following 
properties: 

1st. They give, with ferric salts, a black coloration 
approaching blue or green. 

2d. They precipitate solutions of albuminoid sub" 
stances, particularly those of gelatine. 

The principal ones are: 

Tannin of oak, C 2 7H 22 0i 7 . 

" " cachou (catechin or catechic acid). 
" " quinquinia (quinotannic acid). 
" " coffee (caffetannic acid). 
" " fustic (morintannic acid). 

Oak tannin is best prepared from gall-nuts which 
contain much more than does the bark. The nuts 
are pulverized and submitted to the action of commer- 
cial sulphuric ether, which is made aqueous. This 
ether may be replaced with advantage by a mixture of 
600 grams of pure ether, 30 grams of 90 per cent, 
alcohol, and 10 grams of distilled water for every 
100 grams of gall-nuts. After twenty-four hours the 
apparatus contains two layers of liquid ; the upper one 
is ether, containing but little tannin, while the lower 
one is a very strong aqueous solution of tannin. 

The lower layer is removed and evaporated in an 



TANNIN. 197 

oven on shallow plates. Tliere remains an amorphous 
spongy substance, very soluble in water, less soluble 
in alcohol, and almost insoluble in ether. This residue 
is very astringent and slightly acid. 

Solutions of tannin give a white precipitate with 
tartar emetic. 

It precipitates solutions of the alkaloids, and coagu- 
lates blood. 

"With solutions of gelatin it gives a voluminous pre- 
cipitate, soluble on heating in an excess of gelatin. 

Tannin forms, with fresh hide, an imputrescible com- 
pound, which is leather. The art of tanning is based 
on the action of oak-bark tannin on hides from which 
the hair has been removed, usually by lime. 

Gallic acid. In solution, tannin is gradually de- 
composed, the liquid becoming covered with mould. 

Carbon dioxide is disengaged and an acid, called 
gallic acid, is formed. 

This transformation does not take place if all air is 
excluded; and the air alone is not sufficient. It requires 
the presence of a mycelium of a tnucedin conveyed to 
the liquid either by the air or in some other manner. 

This transformation is, like alcoholic fermentation, 
a phenomenon correlative with the development and 
growth of an organism. On boiling tannin with water 
acidulated with hydrochloric or sulphuric acid, it is 
decomposed into glucose and gallic acid: 

C 27 H 22 17 + 4H 2 0=3(C 7 H 6 5 ) + C 6 H 12 6 . 

V „ J 



Gallic acid. Glucose. 



198 ORGANIC CHEMISTRY. 

Gallic acid is deposited as the liquid becomes cool. 
It is purified by redissolving and treating with animal 
charcoal, and recrystallizing. 

Gallic acid, C 7 H 6 5 = xx fx [ 4 , crystallizes in silky 

needles, soluble in three parts of boiling water, but 
little soluble in cold water. This solution, on standing 
in the air, becomes altered after a long time, carbon 
dioxide is disengaged and the solution turns brown ; 
alkalies accelerate this change. 

Gallic acid produces a blue color with ferric salts, 
and precipitates tartar emetic, but does not precipitate 
gelatin when pure, nor the alkaloids. 

Mixed with pumice-stone and heated to 210° it pro- 
duces a beautiful sublimate of jpyrogallic acid, carbon 
dioxide being liberated at the same time. 

C 7 H 6 O 5 =C 6 H 6 O 3 + C0 2 . 

This body occurs in colorless, acicular crystals, 
fusible at about 115°, and soluble in 2.5 parts of 
water. Its solution absorbs oxygen from the air, in 
presence of alkalies, and becomes quite brown. 

It reduces gold and silver salts, and forms unstable 
compounds with certain acids. It may properly be 
placed among the phenols. This body is employed 
in photography, and in the laboratory. JVIercadante 
(47-74-484:) finds that gallic acid is injurious to 
vegetation, inasmuch as it combines with the mineral 
food of the plant rendering it insoluble. 

Grimaux was the first to consider gallic acid as 
tetratomic and monobasic (77-620). 



VEGETABLE CHEMISTRY. 199 



VEGETABLE CHEMISTKY. 

At the moment when the radicle of a plant appears 
above the ground, its vital phenomena undergo a 
marked change. 

The plant decomposes carbon dioxide, water and 
certain nitrogenous compounds furnished by the soil, 
and grows by retaining carbon, hydrogen, nitrogen and 
a little oxygen, and returns to the air the greater part 
of the oxygen derived from the carbon dioxide, water 
and nitrogenous compounds. 

Bonnet observed, in the last century, that leaves, 
exposed to the sun in areated water, disengage a gas, 
which Priestly showed is oxygen. Sennebier discovered 
that this oxygen is derived from carbon dioxide. Be 
Saussure verified these facts, and demonstrated that 
this decomposition of carbon dioxide does not take 
place in the dark, and that the green portions of the 
plant alone are capable of effecting the change. 

J. Belluci (9-78-362) has lately shown that, con- 
trary to former belief, none of the oxygen exhaled by 
plants is in the form of ozone. 

Experiment. — Place a few leaves in a flask half full 
of water containing carbon dioxide, a soda water," invert 
the flask over a glass of water, and expose it to the sun- 
light, after having covered it, if the sun is very hot T 
with a sheet of transparent paper; minute bubbles will 



200 ORGANIC CHEMISTRY. 

soon be seen to form on the leaves, as small as the point 
of a pin, will increase in size, unite and mount to the 
upper part of the flask. Transfer this gas to a test- 
tube, and, on examination, it will be found to be oxy- 
gen. Substitute for this flask an opaque vessel, or per- 
form the experiment in the dark, and the carbon diox- 
ide will not be altered in the least. 

Where do the plants find this carbon dioxide ? 
Chiefly in the air. Boussingault, in order to demon- 
strate this, placed under a bell-glass some peas planted 
in calcined sand; he watered them with pure distilled 
water, and passed air into the glass; the peas grew, 
flowered and bore fruit. 

Now the substance of these peas contained carbon 
hydrogen and nitrogen, in much greater quantity 
than the seed from which they grew, consequently 
these constituents were taken from the air and water. 

If, however, the air be made to pass through an 
alkaline solution before escaping from the vessel, no 
carbon dioxide is absorbed, which also proves that the 
carbon dioxide existing in the air has been removed 
by the plant. The plant takes up, in the same man- 
ner, carbon dioxide from the water which passes from 
the soil into its roots. 

Plants are also capable of decomposing water, in 
fact, Collin and W. Edwards have proved that the sub- 
merged stems of the Polygonum tinctorium and cer- 
tain mushrooms, exhale hydrogen. 

On the other hand, Payen has proved that the hy- 
drogen exceeds the oxygen in the woody parts of 



VEGETABLE CHEMISTRY. 201 

plants, and, indeed, many substances produced by 
plants, as oils and resins, are very rich in hydrogen. 
In short, the oxygen contained in the plant would not 
be sufficient to oxydize or transform into water the 
whole of the hydrogen it contains, consequently it 
must be admitted that water is decomposed by plants. 
The conditions under which this change takes place 
have not as yet been determined. 

The experiment of Boussingault proves, as Ingen- 
housz has claimed, that the air furnishes the plant with 
nitrogen ; but where does this nitrogen come from? Is 
it taken by the plant from the free nitrogen of the atmos- 
phere? or is it derived from the nitric or nitrous acids, 
or from the ammonia contained in the atmosphere, or, 
in one word, from the nitrogenous compounds existing 
in the air? 

Boussingault has shown that while certain families 
of plants, principally the common vegetables, derive 
from the air a large quantity of nitrogen, even taking 
up free nitrogen, others, the cereals for instance, derive 
nitrogen chiefly from the soil; for, on causing clover 
and wheat to grow in calcined sand in presence of air 
deprived of its nitrogenous compounds, and distilled 
water, he observed that the clover took up carbon, hy- 
drogen, water and nitrogen, while it appears that the 
wheat obtained from the air carbon and water only. 

Nitrogen, which is present in the air in the form of 
ammonium nitrate, is absorbed by all plants. Direct 
experiments have shown that the salts of ammonium, 
especially ammonium nitrate, constitute an excellent 



202 ORGANIC CHEMISTRY. 

compost, and consequently this nitrate can lose its oxy- 
gen, or become reduced in. the plant. 

Now, it is known that urea and animal excreta are 
transformed into ammoniacal compounds on exposure 
to the air; therefore, in order to obtain a good crop, 
even with plants which take up the nitrogen of the air, 
it is necessary to employ manures which furnish not 
only easily assimilated nitrogen, but those which, be- 
sides, furnish the plant with soluble organic com- 
pounds and the mineral substances necessary for its 
development and growth. Of these latter there is re- 
quired for the plant, potassium and calcium chlorides, 
sulphates, phosphates, etc. 

With the four elements, carbon, hydrogen, nitrogen,, 
and oxygen, nature forms an infinite variety of com- 
pounds by mysterious methods, to which we have not, 
as yet, the key, but of which synthetical research gives 
us some idea. Thus, with carbon dioxide and water, 
Berthelot produces formic acid; with formic acid he 
obtains alcohol, and subsequently acetic acid. Pasteur 
also has shown that glycerine, one of the principles of 
fat, is produced in the process of fermentation and 
that a complex acid, succinic acid, is also formed under 
the same circumstances. However, we are far from 
knowing how to produce those substances which nature 
forms at ordinary temperatures, and with only four 
elements. What wondrous chemistry is that of the 
plant, fitted by an all-wise Creator to elaborate with 
such simple materials, the beauteous violet, the fragrant 
rose, or the luscious fruit ! 



VEGETABLE CHEMISTRY. 203 

By combining six atoms of carbon with five atoms 
of water, nature forms either the woody principle, cel- 
lulose, or the essential constituent of the potato, starch. 
By uniting ten atoms of carbon with sixteen atoms of 
hydrogen, she produces, in the orange and in the pine, 
two essences or oils very different in character. By 
associating the four organic elements she forms the 
most different substances, the nourishing cereal as well 
as the most deadly strychnia; and often products as 
unlike as these are found side by side in the same 
plant. 

Thus the plant is a structure which decomposes car- 
bon dioxide, water, and compounds of nitrogen; which 
forms its substance out of carbon, hydrogen, nitrogen, 
and a part of the oxygen of these compounds, and 
which exhales oxygen. Hence, chemically, it would be 
proper to call the plant a reducing apparatus. 

We should add that the flowers and portions of 
plants not green, also the buds in developing, produce 
an exhalation of carbon dioxide, and that during ger- 
mination, and especially during the time of flowering, 
a sensible amount of heat is disengaged. As a result 
of this elevation of temperature, there is produced in 
plants some slight oxydation or combustion, as in the 
respiration of animals. 

Hence, we must conclude that plants and animals, 
in many circumstances at least, deport themselves in 
•a similar manner. 

Many experimenters, and especially Dutrochet and 
Garreau, go further, and say that plants and animals 



204 ORGANIC CHEMISTRY. 

respire in an identical manner, and according to their 
theories all living creatures take np oxygen and exhale 
carbon dioxide. 

The experiments of Garreau especially deserve at- 
tention. He placed branches, detached or affixed to 
the plant, in vessels full of air, and exposed them to a 
diffused light. The volume of the air was known and 
the oxygen absorbed was determined by a special con- 
trivance ; the carbon dioxide produced was removed 
by placing in the vessel an alkaline solution of known 
weight. Thus the variations of these gases were care- 
fully studied. 

As a result of his experiments Garreau claimed to 
have established that both in the dark and in the 
light, there is an absorption of oxygen and an ex- 
halation of carbon dioxide, but the amount of car- 
bon dioxide collected does not represent the amount 
really exhaled, as the greater part is reduced at the 
moment of liberation. From these facts it would 
appear that in all living creatures the same phenome- 
non of respiration takes place, which consists in a 
consumption of oxygen and an exhalation of carbon 
dioxide. 

This phenomenon is associated with another ; viz., 
assimilation or nutrition. It is here that the differ- 
ence, indeed a complete opposition, between the two 
kingdoms is established. The plant grows by re- 
ducing, under the influence of heat and sunlight, 
carbon dioxide, water and nitric acid, by accumulating 
carbon, hydrogen, nitrogen and by exhaling the greater 



ORGANIZED SUBSTANCES. 205 

part of the oxygen. The animal, on the other hand, 
forms its substance from that of the plant, oxydizing, 
or consuming, the vegetable products with the oxy- 
gen of the air exhaled by the plants; it reduces the 
complex products formed in the vegetable to the state 
of carbon dioxide, water and ammonia; thus the ani- 
mals supply the plants with food, receiving in turn 
nourishment from them. Those desirous of further 
studying this and other interesting topics relating to 
Vegetable Chemistry, will find very valuable the 
works of Prof. S. "W*. Johnson, " How Crops Grow," 
and "How Crops Feed"; also Prof. John C. Draper's 
article in Am. Jour. Sci. and Arts, 'Nov. 1872, entitled 
u Growth of Seedling Plants." 

ORGANIZED SUBSTANCES. 

Among the chemical substances of which we have 
spoken certain ones participate more in vital phe- 
nomena, and have more definite physical structure than 
do others. 

These are designated as organized or organizdble 
substances, the term organic being reserved for the 
definite compounds studied in organic chemistry. All 
these substances play an important part in the veget- 
able kingdom, forming the network of vegetable tis- 
sue, as cellulose or as starch, etc. 

CELLULOSE OR CELLULIN, (C 6 H 10 O 5 ) n . 

On examining a young plant under the microscope, 



206 OKGANIC CHEMISTRY. 

we observe that it is built up of little cells and mi- 
nute, diaphanous ducts or vessels filled with sap and 
air. The material of which these tissues are com- 
posed is called cellulose. The pith of the elder, cot- 
ton fibre, and paper are almost exclusively composed 
of this substance. 

Cellulose is a carbo-hydrate ; C 6 H 10 O 5 , is the 
formula, ordinarily given to it, although a multiple 
formula at least three times as large, or C 18 H 30 O 15 is 
necessary to explain certain reactions with nitric acid. 

Experiment. Pure cellulose may be obtained in the 
following manner : cotton, linen or paper is treated with 
dilute alkaline solutions, washed and immersed in weak 
chlorine water; finally it is submitted to the action of 
various solvents, as water, alcohol, ether and acetic 
acid until nothing more is dissolved. 

This substance is solid, white and insoluble. It is 
destroyed at a red heat, producing carbon and numer- 
ous carbohydrides, gaseous and liquid, which distil 
over. With monohydrated sulphuric acid it produces 
a colorless, viscid liquid, which contains, at first, an 
insoluble substance having the properties of starch and 
yielding a blue color with iodine. If the action of the 
acid is continued, the whole is dissolved and the same 
products are obtained as in the case of starch when 
brought in contact with sulphuric acid, i. e. dextrin 
and glucose. To separate the latter substance, it is 
simply necessary to saturate the acid with chalk and 
evaporate the liquid. 

Concentrated hydrochloric acid produces the same 



CELLULOSE. 207 

effect. If paper be immersed for an instant only in 
sulphuric acid, diluted with half its volume of water, 
and carefully washed, it acquires the toughness of 
parchment. Paper thus prepared is frequently 
employed in experiments on dialysis ; it is also much 
used by pharmacists to cover the stoppers of bottles. 
It is known in commerce as vegetable parchment, 

GUN COTTON OR PYROXYLIN. 

Gun cotton was first made by Schoenbein, in 1846. 

To prepare it cotton is plunged for two or three 
minutes into fuming nitric' acid, or, better, into a mix- 
ture of 1 vol. nitric acid (of a density of 1.5), and 2 
vols, of strong sulphuric acid; it is then thoroughly 
washed and dried at a low temperature. 

The cotton is not changed in appearance other than 
becoming -somewhat wrinkled. When well prepared 
it burns completely, leaving no residue. The tem- 
perature at which it takes fire varies from 100° to 180° 
according to the manner in which it has been pre- 
pared. It is cellulose in which from six to nine atoms 
hydrogen have been replaced by an equivalent quan- 
tity of the monad radicle N0 2 that, having the 
formula C ]8 H 21 15 9E"0 2 , has the greatest explosive 
energy. Pyroxylin regenerates cellulose in contact 
with ferrous chloride. If cellulose be considered a sort 
of alcohol, as claimed by some, pyroxylin would be a 
nitric ether of this alcohol. 

Pyroxylin has the advantage over gunpowder of 



208 ORGANIC CHEMISTRY. 

being more easily prepared, and of remaining unaf- 
fected by moisture, but its cost is relatively greater, 
and its shattering power renders its employment 
dangerous. 

The term collodion (from xoWa, glue) is given to a 
preparation obtained by dissolved gan-cotton in a 
mixture of 1 part of alcohol and 4 parts of ether, 

Chas. H. Mitchell has made (52-74-235) a number 
of experiments, with the view of ascertaining the rela- 
tive proportions of cotton and acid, together w r ith the 
proper time of maceration necessary to produce a 
cotton which should combine the largest yield with 
the highest explosive power and solubility. 

The following formula was at length adopted: 

Raw cotton, - - . 2 parts. 

Potassium carbonate, - - 1 " 

Distilled water, - - - 100 " 

Boil for several hours, adding water to keep up the 
measure ; then wash until free from any alkali, and 
dry. Then take of — 

Purified cotton, - - - - 7 oz. av. 

Nitrous acid (nitric, saturated with nitrous acid), 
s. g. 1.42, 4 pints. 

Sulphuric acid, s. g. 1.84, - - - 4 " 

Mix the acids in a stone jar capable of holding 2 gals., 
and when cooled to about 80° Fahr., immerse the cot- 
ton in small portions at a time ; cover the jar and 
allow to stand 4 days in a moderately cool place (temp. 
50° to 70° Fahr.) then wash the cotton in small poi- 



CELLULOSE. 209 

tions, in hot water, to remove the principal part of the 
acid; pack in a conical glass percolator, and pour on 
distilled water until " the washings are not affected by 
solution of barium chloride. 

Collodion, on spontaneously evaporating, forms a 
transparent and impermeable membraneous coating, 
and is much employed in photography, also somewhat 
in surgery. 

Cellulose is attacked by chlorine; the use of solu- 
tions of chloride of lime, and of chlorine, in large 
quantities in washing, or bleaching, will cause a rapid 
deterioration of linen or cotton goods. 

Schweizer has shown that cotton, paper, etc., is 
very easily dissolved by an ammoniacal solution of 
copper. Attempts by the author to employ this 
solution for a fc water-proof " coating of fabrics, as has 
been suggested, failed to yield a satisfactory result, on 
account of the liability of the coating to crack and 
peel off. 

Peligot has found in the skin of silk worms, and 
Schmidt has discovered in the envelopes of the 
Tunicates, a substance, tunicine, which has the com- 
position and properties of cellulose. 

Linen, hemp, cotton, wood and paper are all essen- 
tially cellulose. 



210 OEGANIC CHEMISTRY. 



AMYLACEOUS SUBSTANCES. 

These substances are almost universally present in 
plants; particularly that known as starch oifecula. 

The potato yields about 20 per cent, of starch. In 
order to obtain it, this root is grated and the pulp 
placed upon sieves, arranged one above the other, and 
through which a stream of water flows. 

The grains of starch being extremely minute pass 
through the meshes of the sieve, while the walls of the 
cells remain behind. The starch is washed, drained, 
and dried, first at ordinary temperature, afterwards by 
the application of a moderate heat. 

Starch. a?(C 6 H 10 O 5 ) probably C 18 H 30 O 15 . Flour 
contains, besides starch, nitrogenous substances, de- 
nominated gluten; this gluten is capable of ferment- 
ing, whereupon it becomes soluble, while the starch 
remains unaltered and insoluble. Under these con- 
ditions the gluten gradually dissolves, disengaging 
ammoniacal compounds, hydrogen sulphide and other 
products of putrefaction. 

At the end of twenty or thirty days, the gluten 
having become dissolved, the liquid is removed, and 
the starch, washed and dried, shrinks into columnar 
fragments, which are readily pulverized by gentle 
pressure. 



STAECH. 211 

A more modern method is that employed in France, 
which is essentially the same as the process cited above, 
as that used in making potato starch here. The water 
carries away the starch while the gluten remains be- 
hind in the form of an elastic mass, which is also util- 
ized. For this purpose it is incorporated with flour 
poor in gluten, to be made into macaroni, and for the 
manufacture of a very nutritive preparation, " granu- 
lated gluten;" it is also employed, according to the 
recommendation of Bouchardat, in making bread for 
persons afflicted with diabetes. 

Starch, examined with a microscope, exhibits flat- 
tened ovate granules of different size in various plants, 
but always very small. Those of the Rohan potato 
have a length of 0.185 mm.; the smallest are those of 
the Chenopodium, quinoa whose length is 0.002 mm. 

When starch is heated with water to 70°, the gran- 
ules increase from 20 to 30 times their original volume, 
and become converted into a tenacious paste. A small 
quantity of the starch passes into solution, and to this 
the name amidin has been given. Starch paste and 
the solutions of starch have the characteristic property 
of becoming blue in contact with small quantities of 
iodine. The liquid becomes colorless at about 70°, but 
regains its color on cooling. If to this blue liquid a 
solution of a salt, sodium sulphate for instance, be 
added, we obtain a dark-blue floculent precipitate. This 
substance, called starch iodide, is not a chemical com- 
pound, but a sort of lake, containing variable quanti- 
ties of iodine diffused throughout the starch and solv- 



212 ORGANIC CHEMISTRY. 

ent. This reaction with iodine is a very valuable test 
for starch, but is open to several fallacies, and apt to 
mislead in inexperienced hands. 

Until lately, it has been claimed that starch is insol- 
uble in water, and that if water in which starch has 
been boiled gives with iodine the characteristic reaction 
of this substance, it is due to particles of starch suffi- 
ciently minute to pass through the pores of the filter. 
But the results of the experiments of Maschke and 
Thenard, show that if starch is heated for some time 
at 100°, it is partially transformed into a variety solu- 
ble in water. This substance is colored by iodine; it 
furnishes, on evaporation, a gummy solid which is pre- 
cipitated by alcohol as an amorphous powder. 

If we boil starch for a long time with water it is 
converted into a substance called dextrin. The pres- 
ence of a small per centage of sulphuric acid facilitates 
this change, which is soon followed by the transforma- 
tion of the dextrin into glucose. The sulphuric acid 
is not at all altered during the reaction. 

The change of starch into glucose also takes place 
when water containing starch, and to which germinated 
barley has been added, is heated to about 70°. 

This transformation is clue to a substance called 
diastase (from. SiaaraffiS, separation), which is formed 
in the seed during germination. The production of 
diastase on the formation of the young shoot, explains 
how starch becomes soluble and serves as nutriment to 
the young plant. 

The ptyalin of the saliva, the pancreatic juice, the 



STARCH. 213 

soluble parts of beer yeast, gluten, and many other sub- 
stances, are capable of producing this transformation 
of starch into dextrin and glucose. 

It has generally been considered that the molecule 
of starch, in being transformed into glucose, simply 
united with one molecule of water directly, thus: 

C 6 H 10 O 5 4-H 2 O=C 6 H 12 O 6 . 

Musculus, however, claims to have established that 
the starch is first transformed into a soluble metamer, 
and this, thereupon, splits up into dextrin and 
glucose ; 

Ci 8 H 30 O 15 + H 2 O=2C 6 H 10 O 5 -f C 6 H 12 6 . 



Dextrin. Glucose. 

By further action, the whole of the dextrine becomes 
converted into glucose, (2-[3] 60-203). 

Starch, heated simply to about 160°, is also changed 
into dextrin. 

It is attacked by dilute nitric acid, nitrous vapors 
are given oiF and different substances are produced, 
chiefly, however, oxalic acid. 

If starch is agitated with fuming nitric acid, it is 
dissolved and water precipitates from the solution a 
nitrous compound which is explosive. 

The alkalies, in concentrated solutions, when heated 
with starch disorganize and dissolve it. Solutions con- 
taining two to three per cent, of alkali, accelerate the 
formation of starch paste. 



214 ORGANIC CHEMISTRY. 

Starch is employed in the laundry and therapeutic- 
ally in poultices, injections and baths. 

Tajpioca is the starch of the root of the Jatropa 
mamhot, called cassava or manioc. 

Sago is obtained from the pith of various sago 
palms. 

Arrow-root is the starch of the Maranta arundi- 
nacece^ and one or two other tropical plants. 

Salep is obtained irom the Orchis mascula. 

Intjlin. There has been found in the roots of the 
Jerusalem artichoke, of the chicory, and the bulbs of 
the dahlia, a substance isomeric with starch, called 
inulin. 

Lichenin. There is extracted from certain lichens 
and mosses a substance called lichenin, which has the 
property of swelling in cold water and of being dis- 
solved in boiling water. It is prepared by treating 
Iceland moss with ether, alcohol, a weak solution of 
potassa, and finally with dilute hydrochloric acid. 

There exists in the animal organism a variety of 
starch designated by the name of glycogen. 

DEXTRIN, OR DEXTRINE. 

C 6 H 10 O 5 . 

To prepare dextrin, starch may be heated with 
water containing a small quantity of sulphuric or 
oxalic acid ; the operation should be arrested when 
the liquid gives with iodine only a wine-colored re- 
action. 



FLOUR. 215 

For the acids, a small quantity of germinated bar- 
ley may be substituted, placed in a bag immersed in 
the liquid. Dextrin thus prepared always contains 
glucose. It may be obtained free from this substance 
by heating starch with ■$■ its weight of water and 1 2 - 
of nitric acid. 

Dextrin is amorphous, slightly yellow, very soluble 
in water, insoluble in alcohol and concentrated ether. 

It is used somewhat in preparing bandages in case 
of fracture, and very extensively as a paste for calico- 
printers. 

Dextrin, forms viscid adhesive solutions which are 
used for the same purposes as gum-arabic. The mu- 
cilage used by the U. S. government for postage 
stamps is composed of dextrin two ounces, acetic 
acid one ounce, water five ounces, alcohol one ounce. 
Dextrin may be distinguished from gum-arabic by 
not being precipitated on adding a dilute solution of 
lead acetate, and by furnishing with nitric acid a so- 
lution of oxalic acid and not a precipitate of mucic 
acid. 

FLOUR. 

Amylaceous substances are of great importance as 
food. Wheat and other cereals are the most import- 
ant sources of these aliments. 

Starch, as also sugar and the neutral carbohydrates, 
are respiratory foods whose principal effect is the pro- 
duction of heat by being oxidized, or burned, in the 
body. 



216 ORGANIC CHEMISTRY. 

The composition of four of the leading cereals is 
herewith given : 





1 


CO 


£ u 


o 


COZ 
oo O 

c a 




CO 

& 




<t> 




2*3". 

CD p 


so 


So 

. on 




S3 


Wheat, 


,14.0 


59.5 


7 


1.7 


14 


1.2 


i.5 


Eye, 


16.0 


57.5 


10 


3.0 


9 


2.0 


2.0 


Oats, 


14.0 


53.5 


8 


4.0 


12 


5.5 


4.0 


Bice, 


14.5 


rr.o 




0.5 


7 


0.5 


0.7 



The sticky, elastic substance found with starch in 
flour is gluten (called also glutin), and is a mixture 
of various proximate compounds, but chiefly of three; 
legumin, or vegetable casein, fibrin and gelatine. 

Flour of good quality is dry and soft to the touch; 
it forms with water an elastic, non-adhesive dough. 

The value of flour depends largely upon the gluten 
it contains, though not as stated in most authors upon 
the percentage of this substance, but upon the quality 
rather, as shown by recent investigations of R. "W. 
Kunis (26-74-1487). 

The modern "patent process," originating in Min- 
nesota, is mainly a method of grinding which intro- 
duces into the flour more gluten than in older pro- 



cesses. 



GUM. 



CfiHmOt;. 



This substance is very widely distributed in the 
vegetable kingdom. Gums either swell in water or 



GUM. 217 

are dissolved, imparting to it a mucilaginous consis- 
tency. 

From a chemical standpoint they are essentially 
characterized by giving a precipitate of mucic acid 
on being boiled with nitric acid, and by precipitating 
lead subacetate. 

Gum-arabic, ARABiN. This gum exudes from dif- 
ferent species of acacias, as Acacia arahica, A. sene- 
galensis, A. vera / it is obtained from Arabia and 
Senegal. 

According to Fremy, gum-arabic is a salt formed 
by the combination of an acid, gummic or arable acid, 
with lime and potassa. This acid may be isolated by 
pouring hydrochloric acid into a solution of gum, and 
adding alcohol; an amphorous deposit is formed which, 
dried at 120°, has the formula C 6 H 10 O 5 . This acid is 
very soluble in water. Its solution is levogyrate, like 
that of gum-arabic. On being heated to 150° it is 
transformed into a substance insoluble in water called 
meta-gummic acid, whose salts are likewise insoluble. 
Gum-arabic gives with ferric salts an orange-colored, 
floculent precipitate soluble in acids. 

Ceeasin. The gum which exudes from cherry and 
plum trees is a mixture of soluble gummates and in- 
soluble meta-gummates ; hence it is only partially 
soluble in water. 

Cerasin becomes soluble on being boiled with water, 
as the meta-gummates are transformed into gummates 
by the action of boiling water. 

These gums heated with dilute sulphuric acid furnish 
a dextrogyrate sugar. 



218 OEGANIC CHEMISTEY. 

Gum-tragacanth often contains starch. 

Mucilage or Bassorin. There exists in the seeds 
of the quince and flax, in the roots of the marsh-mal- 
low and in portions of many other plants, a substance 
or substances, which, exposed to the action of boiling 
water, furnish a thick mucilage, which appears to con- 
sist of a soluble, together with an insoluble substance. 
Nitric acid converts this mucilage into mucic and ox- 
alic acids. Gum and mucilage are frequently em- 
ployed as emollients, and in syrups, also extensively 
in confectionery. 

Pectin Group. Many roots, as the carrot, beet, 
etc., also green fruits, contain a neutral gelatinous 
substance, insoluble in water, alcohol and ether, called 
pectose. It is that which gives to green fruits their 
harshness. This substance is modified during the 
ripening of the fruit and becomes soluble, vegetable 
jelly, or pectin (from ar/KriS, a jelly), to which 
Fremy assigns the formula C 32 H 48 3 2. 

Pectinj submitted to the action of a ferment found 
in the cellular tissues of vegetables, called pectase, or 
of cold, very dilute, alkaline solutions, is changed into 
a gelatinous acid called pectosic acid, then into 
another substance likewise gelatinous, which is known 
by the name of pectie acid. All these substances are 
amorphous, and non -nitrogenous. Their formulae are 
not yet definitely determined. 

According to Fremy, to whom we are indebted for 
the foregoing facts, the jelly obtained from the current 
and other fruits is due to the action of the pectase on 
the pectin of these fruits. 



LEGUMHST. 219 

These substances resemble gums in producing, on 
boiling with nitric acid, a precipitate of mucic acid. 

Much doubt still exists respecting the composition 
of the pectin group. 

LEG-UMIN OR VEGETABLE CASEIN. 

Legumin is found in most leguminous seeds, such 
as sweet and bitter almonds; also in beans, peas, etc., 
the latter containing about 25 per cent. It is con- 
sidered to be identical with casein by Liebig and 
Wbehler. 

It may be obtained by digesting coarsely powdered 
peas in cold or tepid water for two hours, allowing 
the starch and fibrous matter to subside^ and then 
filtering the liquid. It forms a clear, viscid solution, 
which is not coagulated by heat unless albumen is also 
present, but, like emulsin and unlike albumen, it is 
precipitated by acetic acid. It is coagulated by lactic 
acid, also by alcohol; in the latter case the precipitate 
is redissolved by water. 

Acetic acid, diluted with 8 to 10 parts of water, is 
carefully dropped into the filtered solution obtained 
above, and the legumin is precipitated; an excess of 
the acid should be avoided, as this would dissolve the 
precipitate. It falls in the shape of white flakes, and 
after having been washed on a filter should be 
dried, pulverized and freed from adhering fat by 
digestion in ether. Legumin may be obtained from 
lentils with the same facility as from peas; but it is 



220 ORGANIC CHEMISTRY. 

less easily procured from beans (haricots), in con- 
sequence of their containing a gummy matter which 
interferes with its precipitation and with the filtration 
of the liquids. 

The chemical properties of legumin are identical 
with those of casein. 

Liebig supposes that grape-juice and other vegetable 
juices which are deficient in albumen, derive their 
fermentation power from soluble legumin. This 
principle is soluble in tartaric acid, and to its presence 
he ascribes the tendency of sugar to form alcohol and 
carbon dioxide instead of mucilage and lactic acid. 

VEGETABLE ALBUMEN. 

Vegetable albumen is contained in many plant- 
juices and is deposited in flocculi on applying heat to 
such liquids. It can also be precipitated by nitric 
acid, tannin and mercuric chloride precisely like animal 
albumen. Vegetable albumen is composed of carbon, 
hydrogen, nitrogen, oxygen and sulphur. There is no 
trustworthy formula for this substance. 



ANIMAL CHEMISTRY 



ANIMAL CHEMISTRY. 



The substances serving as materials to build up the 
structure of animals are of a varied nature ; they may, 
however, be grouped into four classes : 

I. FARINACEOUS AND SACCHARINE. 
II. FATTY. 

III. NITROGENOUS. 

IV. MINERAL. 

We have already studied the first, second, and 
fourth of these classes ; we will now proceed to examine 
those of the third. 

NITBOGKENOUS SUBSTANCES. 

It is generally considered that these substances act 
a different part in the organism from that of the 
saccharine and fatty bodies, these latter serving ex- 
clusively as heat producers, and being decomposed 
and ultimately consumed (oxidized) in the respiratory 
process, have therefore received the name of respiratory 
foods. The nitrogenous principles (albumen, casein, 
fibrin, etc.) serving to form the tissues have, likewise, 



224 ANIMAL CHEMISTRY. 

received the denomination plastic foods. The distinc- 
tion thus made is too restricted, as we shall show 
later. 

Dumas and Oahours have proven that the cereals 
and other plants employed as food contain similar 
principles to those found in flesh, and especially that 
albuminoid matter exists in plants as well as animals. 

The albumen of the blood and that of wheat are 
alike. In the gluten of wheat albuminoid substances 
are found which are hardly distinguishable from animal 
albumen, fibrin, and casein. 

These substances are characterized : 

1st. By their amorphous structure. The three sub- 
stances mentioned never crystallize ; and as they are 
also non- volatile, it is difficult to form an idea of 
their constitution, and represent them by a formula. 
This formula must necessarily be very complex, as 
sulphur forms a constituent, though present only in 
very small quantity. Lieberkuhn represents their 
composition by the expression 



C 72 H 112 N 18 S0 22 . 



2nd. By their extreme instability. The apparently 
most insignificant circumstance causes them to pass 
from a soluble to an insoluble condition, or vice versa, 
and produces their transformation. They are decom- 
posed with great facility under the action of air and 
water. This very exceptional instability constitutes a 
property of the greatest interest, as it permits these 



NITROGENOUS SUBSTANCES. 225 

substances to take part in a wonderful manner in the 
varied transformations which occur in living organisms, 
and it might be said that they are the principal agents 
of development in animals and plants. We shall pre- 
sently see that, whatever this real albuminoid sub- 
stance may be, it is transformed in the stomach into 
identical substances — peptones; also, that during the 
incubation of the egg the albumen is seemingly changed 
into fibrin. 

Classification. — The albuminoid substances are 
very numerous, and may be classed into two groups. 
Those of the first group contain : 

Carbon . . . . .53.5 

Hydrogen 6.9 

Nitrogen . . . . .15.6 

Oxygen 24.0 



100.0 



They contain, besides, 0.4 to 0.5 per cent, of sulphur, 
unlike those of the second group, which usually contain 
no sulphur. In addition, they often contain small 
quantities of mineral substances. 

The first are more specially designated by the 
name of albuminoid substances, as albumen is the 
most characteristic member of the group. They are 
also known by the name of protein substances, because 
Mulder claimed they might be considered as formed 
of a single radical protein, to which are united 
variable proportions of sulphur, phosphorus, etc. 



226 ANIMAL CHEMISTEY. 

The principal members of this group are : albumen, 
of which several modifications are recognized — the 
paralbumen, metalbumen, etc. ; fibrin, of which there are 
several kinds — the fibrin of the blood, fibrin of the 
muscles or myosin ; casein, regarded by some as a com- 
bination of albumen and alkali ; hemoglobin or hemato- 
crystallin, the colouring matter of the blood, which is 
distinguished from most other albuminoid substances 
by its property of crystallizing ; vitellin, the principle 
of the yolk of an egg ; also, several principles, icthin, 
icthlin (IxQvs, a fish), emydin, the first two obtained by 
Valenciennes and Fremy from fishes' eggs, the latter 
from the eggs of the turtle. 

The composition of these substances is identical or 
very similar; a formula cannot be given with pre- 
cision. 

The substances of the second group generally contain 
less sulphur, often none, and appear to be derived 
from the first by the addition of nitrogen and oxygen. 
They contain in per cent. : 

Carbon . . • . . . 50.0 

Hydrogen . . • . 6.3 

Nitrogen 16.8 

Oxygen ;--...... 26.6 

100.0 

In this group we find — ossein, the organic substance 
of bones, which is converted into gelatin by the action 
of boiling water ; cartilage, a substance very analogous 



NITROGENOUS SUBSTANCES. 227 

to the latter, and which is transformed by boiling 
water into chondrin ; various principles concerned in 
the digestive phenomena, as the ptyalin of the saliva, 
the pepsin of the gastric juice, the mucin of the mucus, 
the pyin of pus, etc.; together with different pro- 
ducts which result from the action of the gastric juice 
upon nitrogenous substances, and which are called 
albuminoses or peptones. 

General Characteristics. — The substances of these 
two groups on being heated give off an odour of burnt 
feathers. On distillation they produce water, empy- 
reumatic oils, and ammonium carbonate, sulphide, and 
cyanide. Carbon remains in the retort. 

The substances of the first group, on being heated to 
50° — 60° with a solution of potassium hydrate, lose their 
sulphur and are dissolved. If we add acetic acid to 
this liquid, dark grey flakes of a substance (protein 
of Mulder) are thrown down. The substances of the 
second group do not possess this property. On pro- 
tracted boiling with a caustic alkali they yield : 



Tyrosin . „ . . C 9 H n NO s 
Leucin .... C 6 H 13 N0 2 
Glycocol .... C 2 H 5 N0 2 



Some are soluble, others insoluble, in water ; they are, 
in general, insoluble in alcohol, ether, and chloroform. 

Hydrochloric acid diluted with 1,000 times its weight 
of water dissolves some, a few swell up simply ; upon 
others it has no effect. Hot concentrated hydrochloric 



228 ANIMAL CHEMISTRY. 

acid attacks all these substances, and the resulting pro- 
ducts are the same as those which are obtained (and 
more readily) with sulphuric acid. These products are 
chiefly glycocol, leucin, and tyrosin. Nitric acid 
colours them yellow (xanthoproteic acid). Ordinary 
phosphoric and acetic acids do not precipitate the 
substances of the second group, but redissolve them 
even when coagulated. 

Solutions of albuminoid substances in potassium 
hydrate do not precipitate copper salts. Heated with 
oxidizing reagents, as a mixture of potassium bichro- 
mate and sulphuric acid, they furnish several members 
of the series of fatty acids, and the aldehyds corre- 
sponding to these acids. The albuminoid substances are 
decomposed during the process of respiration in the 
same manner as when under the action of oxidizing 
agents. 

Ammoniacal solutions of copper dissolve albuminoid 
substances as they dissolve cellulose, which fact would 
seem to connect the albuminoid substances with cellu- 
lose, and to give certain weight to a theory of Hunt, 
which considers the albuminoid substances as cellulose 
which has combined with the elements of ammonia and 
parted with the elements of water. 

ALBUMEN. 

This substance is found both in vegetable organisms 
(cereals) and in animal organisms (serum of the blood, 
white of egg, lymph, chyle). 



ALBUMEN. 229 

Wurtz obtains it by mixing white of eggs with 
twice its weight of water, straining and precipitating 
the albumen with a solution of lead acetate. The 
precipitate is washed with cold water and decomposed 
with a current of carbon dioxide, which precipitates the 
lead, while the albumen remains in solution. If this 
liquid be evaporated at a temperature below 59°, it is 
deposited in a soluble state ; if a quantity be heated to 
63°, a portion of the albumen is coagulated ; but if the 
temperature is not raised above 74°, four-fifths remain 
dissolved ; consequently it would seem as though there 
were several kinds of albumen, but the nature and 
amount of foreign substances present are the principal 
causes of these differences. If the solution is very dilute, 
coagulation will not take place. Heating is not the 
only mode of producing this change ; alcohol, acids — 
with the exception of a few, such as hydrogen phos- 
phate, H 3 P0 4 , hydrogen tartrate and hydrogen acetate — 
the metallic salts, creosote, tannin, etc., also effect it. 
The alkalies prevent this action. Gautier obtains albu- 
men by dialysis. 

Soluble albumen is without odour, and is more soluble 
in saline than in pure water. Very dilute hydrogen 
chloride precipitates solutions of albumen, the precipi- 
tate being redissolved by an excess of the acid. This 
solution does not contain albumen, but a substance 
probably isomeric with it, which is, however, more 
easily obtained from muscular tissue : it is called 
syntonin. 

Among the products of the putrefaction of albumen, 



230 ANIMAL CHEMISTRY. 

Nencki (18- 7 8-71) has obtained butyric and vale- 
rianic acids. 

Insoluble albumen heated with water in a sealed tube 
to 150° or 160°, dissolves, but this modification is not 
coagulated again by heat. 

Animal albumen containing 1.5 per cent, of soda 
may be regarded as a weak acid, and in presence of 
alkaline solutions it dissolves. A few drops of potassium 
hydrate are sufficient to form with albumen a gela- 
tinous compound, called potassium albuminate, which 
is soluble in water and no longer coagulable by heat. 
This liquid, diluted with water, is rendered turbid by 
acetic acid, but the precipitate is redissolved by an 
excess of acid. 

Albumen of the Serum. — This is easily soluble in con- 
centrated hydrochloric acid, and is not precipitated 
by ether. Injected into the veins it is absorbed. 

Egg Albumen. — This is more difficultly soluble in 
concentrated hydrochloric acid, and is precipitated by 
ether. Injected into the veins it is absorbed in very 
minute quantities, and can be found again in the 
urine. 

Albuminoid substances (fibrino-plastic substance, 
flbrinogene) are found in the blood; they have the 
general characteristics of albumen, but are distinguished 
from it by being precipitated with carbon dioxide. The 
soluble matter of the crystalline lens of the eye also 
possesses this property. 

The coagulation of albumen by alcohol, tannin, and 
heat, and the consequent formation of a sort of net- 



FIBRIN. 231 

work which fills the whole liquid, and which precipi- 
tates all matters held in suspension, as well as certain 
substances in solution, explains the employment of 
white of egg for the clarifying of wine, syrups, 
also as a mordant, and the use of blood in sugar 
refining. 

FIBRIN. 

The blood of animals coagulates spontaneously 
shortly after leaving the body. This is due to the 
solidification of a substance called fibrin, which, on 
solidifying, forms a sort of net- work, imprisoning the 
globules of the blood, and gives rise to a gelatinous 
mass (clot). The researches made to explain this 
process of coagulation will be mentioned further on. 
Ether accelerates this coagulation. Sodium sulphate 
and glycerine retard or even arrest it. Pure fibrin 
may be obtained by beating fresh blood with twigs. 
It attaches itself to the twigs, and if then washed 
with water, and afterwards with alcohol, we obtain a 
dark- grey filamentous substance, which is insoluble 
fibrin. It may also be obtained by working clotted 
blood in water as long as it colours the water. 

Fibrin is insoluble in water, hot or cold, but if 
heated with it in close vessels it gradually loses its 
property of solidifying. It is soluble in alkaline solu- 
tions, and precipitable again by acids. 

Lehman has concluded from his analyses that fibrin 
is oxidized albumen, Smee affirms that if oxygen 
be passed into defibrinated serum, heated to about 



232 ANIMAL CHEMISTRY. 

36°, the albumen is gradually transformed into 
flocks of fibrin. This subject needs further investi- 
gation. 

Fibrin of blood swells when treated with water con- 
taining 1- 1000th part of hydrochloric acid. It is 
dissolved in stronger hydrochloric acid, and is then 
converted into syntonin. Freshly precipitated fibrin 
is dissolved at 35° to 40° in water containing certain 
salts, and notably in that containing potassium nitrate 
or sodium sulphate ; it decomposes hydrogen peroxide. 

The albumen in the egg is transformed into fibrin 
during incubation ; inversely, if fibrin be kept under 
water, it gradually becomes soluble, and this liquid, 
like albumen, is coagulated by the action of heat. 

Varieties of Fibrin. — The gluten which constitutes 
the plastic substance of cereals, has the composition 
and general properties of fibrin. 

When well-washed, muscular tissue is macerated 
with water containing ten parts in 100 of sea salt, 
it is partially dissolved; if this solution is poured 
into water a gelatinous mass is obtained on agitation. 
This substance washed on a filter has received the 
name of myosin, or musculin. 

It is soluble in acids, in dilute alkalies, and in a solution 
of sea salt ; this last solution coagulates at about 60°. 

Myosin, on dissolving in dilute acids, is changed 
into syntonin, which, like myosin, is soluble in acids 
and alkalies, but from which it is distinguished by its 
insolubility in salt water. Syntonin is more easily ob- 
tained by macerating flesh, which has been completely 



CASEIN. 



233 



deprived of blood by prolonged washing with water, 
containing 0.01 of hydrogen chloride. The macerated 
flesh is almost entirely dissolved. This solution is 
filtered and exactly neutralized with sodium carbo- 
nate ; the syntonin is precipitated in a grey, flocculent 
form. 

Blood fibrin contains about : C = 52.6 ; H = 7.0 ; 
N = 16.6; S = 1.2 to 1.6; = the difference, 
authors not agreeing very closely as to its exact com- 
position. 



CASEIN. 



Casein is the nitrogenous principle of milk. To 
extract it, milk is brought to boiling, and a few drops 
of acetic acid added. An abundant coagulum of casein 
mixed with butter (caseum) is formed. The pure 
casein is separated by washing this coagulum several 
times with water, alcohol, and ether. 

Casein is difficultly soluble in water, but is dissolved 
by alkalies. It forms with the alkalies soluble com- 
pounds, and with the other bases insoluble salts. 
Casein has the composition of the albuminates of 
soda, differing, however, from these by various re- 
actions, and by the amount of its levogyrate action on 
the polarized ray of light. 

Solutions of casein are not coagulated by heat, they 
simply become covered with a white film. They are 
precipitated by acetic and other organic acids ; milk 
curdles spontaneously, on account of the lactic acid 
formed in it. 



234 ANIMAL CHEMISTRY. 

Many substances such as tannin, alcohol, plants 
with acid reactions and several others, the flowers 
of the artichoke, of the thistle, of the butterwort 
(Pinguicula vulgaris), and, above all, rennet from 
the stomach of a sucking calf, cause coagulation in 
milk. 

LEGUMIN, OR VEGETABLE CASEIN. 

Braconnot extracted, by means of water, from the 
seeds of leguminous plants (beans, peas) a substance 
called tegumin, and which has a close analogy to casein. 

VITELLIN. 

This substance is prepared by treating boiled yolk 
of egg with ether, which extracts the fatty matters. 
There remains a white substance insoluble in water. 
It can be obtained in a soluble state by mixing fresh 
yolk of egg with water. The clear liquid coagulates 
at about 70°, like albumen, of which it possesses the 
general properties. 

OSSEIN, GELATIN, CHONDRIN. 

The compounds of this second group are probably 
formed of a single substance, whose elements are 
differently aggregated, and also mixed with variable 
quantities of mineral substances. They are insoluble 
in water, alcohol, and acetic acid ; they swell in cold 
and dissolve in hot alkaline solutions. 

The organic substance of bones (ossein), treated with 



OSSEIN, GELATIN, CHONDRIN. 235 

boiling water, furnishes gelatin. The cartilages, under 
the same circumstances, furnish a product which has 
most of the properties of gelatin, but which differs 
from it in being precipitated by acids and by alum ; 
it is called chondrin. 

To prepare gelatin, bones are treated with boiling 
water to remove the grease, then macerated with water 
acidulated with hydrochloric acid, which dissolves the 
mineral portions (calcium carbonate and phosphate). 
The organic portions remain undissolved, retaining the 
form of the bone, yet flexible and elastic. The solu- 
tion is poured off and employed in the manufacture of 
calcium hypophosphite, or of composts. The organic 
substance, well freed from acid by washing in milk of 
lime or a weak solution of sodium carbonate, is put 
into boilers with water, which is gradually raised to 
the boiling point. The organic matter gradually 
enters into solution. It is now decanted into a vat 
heated over a water bath, where various undissolved 
substances are deposited, and whence it is drawn 
into wooden moulds, where it solidifies. The gela- 
tin is removed from the moulds, cut into thin 
slices, dried on nets, and is now the glue of commerce. 

The tendons, skin, horns, and clippings of hides 
are also employed for the manufacture of glue; they 
are simply treated with boiling water. 

Darcet showed in 1817 that gelatin could be 
made directly from bones by digesting them with 
steam heated to 104°. The solution obtained has the 
appearance of soup, and it was hoped to thus pro- 



236 ANIMAL CHEMISTRY. 

duce a very substantial nutriment quite cheaply ; but 
it has been found that the nutritive power of this 
substance is very small, and the use of " gelatine 
food " has been abandoned. 

The purest gelatin is the ichthyocol, or isinglass. 
It is made chiefly in Moldavia and on the borders 
of the Caspian Sea, from the swimming bladders of 
the sturgeon and of the acipenseres. 

Pure gelatin is solid, colourless, and transparent. 
Boiling water dissolves it in large quantities. The 
liquid solidifies to a jelly on cooling : one per cent, 
is sufficient to give water a gelatinous consistency. 
Continued boiling with water deprives it of the pro- 
perty of solidifying in the cold, or gelatinizing. 
Boiled with dilute sulphuric acid, it is transformed 
into glycocol. 



DIGESTION. 237 



DIGESTION. 

An organized being cannot live without nourishment, 
that is, without obtaining from the bodies which 
surround it the materials necessary for the formation 
and the metamorphoses of its tissues. 

The food of animals is rarely assimilable in the state 
in which it is found in nature ; therefore it must 
undergo a preparation which shall render it absorb- 
able. Hence the existence of a particular function, 
digestion. This function is performed by the digestive 
organs. They vary in complexity with different 
animals ; they differ in form according to the nature of 
the food. 

In man the digestive apparatus is very complex. If 
the food is solid it must be dissolved. Every liquid, 
however, is not immediately assimilable ; it often also 
must be transformed in chemical and physical charac- 
ter. We shall now follow the food through the process 
of digestion, and explain the manner in which each 
class of aliments becomes soluble and absorbed. 

SALIVA. 

In the mouth the food is subjected to mechanical 
action under the influence of a liquid secreted by glands 



238 SALIVA. 

situated in pairs on each side of the mouth (parotid, 
submaxillary, and sublingual). 

Tubes have been introduced into the ducts of the 
parotid and submaxillary glands, and by exciting 
secretion, the products of these glands have been 
separately examined. The salivas are not alike, and 
have different digestive properties, their combination, 
mingled with mucus, constituting " mixed saliva." 

The parotid secretion is a clear liquid, not viscous, 
and slightly alkaline, containing 1.0 to 1.6 per cent, of 
solid substances, among which are alkaline chlorides 
and phosphates; an organic substance soluble in 
alcohol and water ; another, ptyalin, which is the most 
important principle of the saliva ; and finally, potassium 
sulphocyanide. 

Ptyalin contains potassium, sodium, and calcium. 
It resembles compounds of albumen with these bases, 
is, however, gelatinous and not coagulable by heat or 
by most metallic salts. It is precipitated by mercury 
bichloride, lead acetate, and tannin. 

The submaxillary glands are dependent upon the 
chorda tympani nerve, and the branches of the great 
sympathetic nerve. The secretion varies as it is excited 
by the one or the other of these nerves. 

The liquid secreted after an excitement of the great 
sympathetic nerve is thick, alkaline, and rich in solid 
substances. The liquid obtained by the excitement of 
the chorda tympani is less concentrated. It is alkaline, 
and contains epithelial cells, small quantities of 
albumen, globulin, and a substance (mucin) to which 



SALIVA, 239 

its mucilaginous appearance is due, and which is not 
found in the parotid secretion. 

The liquid of the sublingual glands has not as yet 
"been obtained pure ; concerning it we know only that 
it is a viscous solution. 

Buccal mucus has a slight acid reaction. 

Mixed saliva is a turbid, ropy, inodorous, tasteless 
liquid. It deposits debris of epithelium. In man its 
density varies from 1.007 to 1.008. 

It has an alkaline reaction, and contains from 0.7 
to 1.0 per cent, of solid substances, of which about 
one-third is inorganic, chiefly alkaline carbonates, 
phosphates, and chlorides. It contains in solution 
more carbon dioxide than even venous blood. 

1,000 parts of saliva contain : — 

Mitscherlich. Jacubowitsch. 
Water . . . 984.50 992.16 
Solid substances . . 10.50 4.84 

Ptyalin . . . 5.25 1.34 

Mucus and epithelium 0.05 1.62 

Sulphocyanogen . . ... 0.06 

According to Longet, potassium sulphocyanide is a 
normal product of the saliva. It is recognized by 
placing in the saliva a ferric salt, which is coloured red. 
This salt does not exist in the blood, perspiration, 
lacrymal fluid, or pancreatic juice. Its amount is 
always very small, and its presence in saliva is doubted 
by Grautier. 



240 ANIMAL CHEMISTRY. 

On boiling saliva it becomes opalescent, on account 
of the precipitation of albumen. Nitric acid colours it 
yellow by attacking the albuminoid substances. Alcohol 
precipitates from it ptyalin, mixed with nitrogenous 
compounds. 

Saliva exposed to the air becomes covered with a 
film of calcium carbonate, and concretions of this 
substance are often found in the salivary ducts and on 
the teeth. 

An adult can secrete about 1,200 to 1,500 grains of 
saliva in twenty-four hours ; the actual quantity varies 
with the dryness of the food. 

The saliva possesses evident mechanical functions in 
digestion. It facilitates mastication by impregnating 
the food ; it lubricates the bolus, and renders degluti- 
tion possible ; and finally, by virtue of its viscous and 
frothy consistency, it imprisons air, which passes into 
the oesophagus with the food. 

Deglutition is favoured much more by the mucus 
than by the saliva proper ; this mucus is secreted by 
glands found in the walls of the mouth and pharynx. 

It has been contested that the saliva has for a 
chemical function the saccharification of starch, as the 
food does not remain but for an instant in contact with 
it, and as the amount of saliva secreted is independent 
of the amount of starch in the food. The proportion of 
saliva increases when the food is dry or hard, and 
diminishes when it is soft, even when it is formed of 
boiled starch ; in short, it seems to vary inversely 
with the humidity of the food. 



SALIVA. 241 

It lias been remarked that salivary glands exist in a 
rudimentary state in animals which, do not masticate 
their food. 

Mialhe indicates the following experiment : Chew 
some unleavened bread, then place it on Berzelius test 
paper. Eub another portion of the same bread with 
water, and filter the liquid. The first is not coloured by 
iodine, and * becomes brown on being boiled with 
potassa. The second turns blue with iodine. 

According to the same chemist this action is due to 
ptyalin, an amorphous substance insoluble in alcohol, 
of which 1 to 2 per cent, is present in the saliva, and 
which is able to saccharify as much as 2,000 times its 
own weight of starch ; it also effects this change with 
extreme rapidity. This substance has then the property 
of vegetable diastase-. 

It has also been shown directly by Messrs. Mialhe, 
Longet, and SchLf, that even if pure gastric juice itself 
does not have the property of saccharifying starch, this 
saccharification by the saliva is not arrested by the 
acidity of the gastric juice, and consequently the saliva 
which is carried into the stomach can continue to 
saccharify the starchy food in this organ. It is then 
very probable that the saliva performs this service in 
the process of digestion, though some claim that this ac- 
tion is only on food not yet thoroughly mixed with gas- 
tric juice. It appears to have no action on sugar, gum, 
cellulose, or albuminoid compounds. 

In inflammatory diseases of the mouth, as in the 
thrush, the saliva becomes acid, and weak alkaline 



242 ANIMAL CHEMISTRYo 

beverages are prescribed. In Bright's disease urea is 
found in the saliva. Mercury is also present in cases 
of mercurial salivation. After the use of preparations 
containing iodine and bromine, these substances are 
found in this secretion. 

The tartar of the teeth contains, in 100 parts, 25 
of organic substances, 75 of inorganic substances, 
formed chiefly of calcium phosphate ; the remainder 
is calcium carbonate, iron, and silica. 

GASTRIC JUICE. 

The gastric juice is secreted in the mucous mem- 
brane of the stomach by an immense number of 
glandular follicles, though not secreted when the stomach 
is empty. 

As soon as food enters the stomach, the mucous 
membrane swells, assumes a blood-red colour, and 
the gastric juice is at once secreted. 

The secretion can also be excited by irritating 
this membrane by ice, cold water, wine, gall, coffee, 
bismuth subnitrate, sodium bicarbonate, and alkaline 
substances in general. According to L. Corvisart, 
gastric juice secreted by mechanical irritation is most 
rich in digestive principles. We can easily procure 
gastric juice, or rather a mixed liquid, formed of this 
juice, stomachic mucus, and saliva, by making an 
aperture in the stomach of an animal, and it may be 
obtained free from saliva by previously ligating the 
oesophagus. 



GASTRIC JUICE. 



243 



The gastric juice may be freed, to a great extent, 
from the mucus by filtration. 

The mucus is alkaline. When the stomach has 
not received food for a long time, the mucous secre- 
tion alone is produced, and the liquid in the stomach 
may become alkaline. The gastric juice forms an 
almost colourless liquid, with a faint odour, decidedly 
acid reaction, and is somewhat denser than water. 
It may be preserved for a very long time without 
alteration, it loses its digestive properties on ebulli- 
tion, but is not altered by cold. 

Schmidt obtained the following analysis of gastric 
juice mixed with saliva : — 





Man. 


Dog. 


Organic matter 


8.79 


17.12 


Hydrochloric acid 


0.20 


3.05 


Potassium chloride 


0.55 


1.12 


Sodium „ . 


1.46 


2.50 


Calcium „ . 


0.06 


.62 


Ammonium „ . 




.47 


Calcium phosphate 


l ( 


1.73 


Magnesium „ . 


0.14 


0.23 


Iron „ . 


1 ( 


0.08 


Water . 


. 988.80 


973.08 



1000.00 1000.00 

These analyses are the mean of several. It is, 
moreover, very evident that the composition of this 
liquid, as well as that of others in the body, must 



244 ANIMAL CHEMISTRY. 

vary, not only in the quantity, but sometimes even 
in the nature of their constituents. 

All analyses of the gastric juice show that it is 
an acid substance. The nature of this acid has been 
the object of much discussion between different 
experimenters, and principally between Messrs. Blond- 
lot and Schmidt. According to the first, the acidity 
is due to acid calcium phosphate ; according to the 
second, to hydrochloric acid. 

It is true that calcium phosphate is found in 
the gastric juice, but according to Lehmann and 
Schiff, this salt is formed by the action of the 
gastric juice on the substance of the bones, and 
does not exist in the gastric juice of animals de- 
prived of this food. Consequently this substance is 
not a normal and constant constituent of gastric 
juice. 

Schmidt points to the following experiment. He 
determines the amount of chlorine in a known weight 
of gastric juice, by means of silver nitrate, and also 
determines the bases. Now, the quantity of hydro- 
chloric acid corresponding to the weight of chlorine 
determined by analysis, is always more than suffi- 
cient to neutralize the bases found; hence he con- 
cludes that hydrochloric acid exists in a free state 
in the gastric juice. 

Moreover, having determined the amount of free 
acid by saturating the gastric juice with a standard 
solution of a base, he found that the amount of free 
acid was about equal to the weight of the excess 



GASTRIC JUICE. 245 

of hydrochloric acid resulting from the previous 
determination. 

Lactic acid is generally found in the gastric juice, 
and, according to Messrs. Bernard and Barreswill, 
this is probably the acidifying principle ; according 
to others, it exists there only when starchy food is used. 
Thus, recently, Eabuteau (9-80-61), by neutralizing 
gastric juice with quinia evaporating, treating with 
amy 1- alcohol, and obtaining the crystallized quinia, 
salt dissolved in the amyl-alcohol, found the free acid 
of the stomach to be hydrochloric acid; he was not 
able to discover lactic acid in the gastric juice. 

Butyric and acetic acids have also been detected in 
the gastric juice. 

When lactic acid is distilled with a dilute solution 
of a chloride, hydrochloric acid is found in the pro- 
duct : possibly the hydrochloric acid is produced in 
the stomach by the reaction of the lactic acid on the 
alkaline chlorides (?). 

It is difficult, according to Eiche, to admit that 
the hydrochloric acid is present in an absolutely free 
state, for calcium carbonate does not completely 
remove the acidity of the gastric juice ; and if this be 
submitted to distillation, the hydrochloric acid comes 
over only as one of the final products. The fact has 
also been directly established that the albuminoid 
substances unite with mineral acids, forming com- 
pounds possessing an acid reaction, and which have 
lost certain properties of free acids. 

B,. Maly (1 — 173, 227) has come to the conclusion, 



246 ANIMAL CHEMISTRY. 

through experiments lately made as to the origin of 
the acid in gastric juice, that pure gastric juice con- 
tains no lactic acid, and that the origin of the hydro- 
chloric acid of the stomach is not due to the decom- 
position of the chlorides present by lactic acid. The 
source of the free hydrochloric acid of the stomach 
is, according to Maly, to be sought in a disasso- 
ciation of the chlorides, without the intervention of 
an acid. 

Charles Bichet, however (62 — '77), has been studying 
the properties of the human gastric juice upon the person 
of the patient on whom Yerneuil successfully performed 
gastrotomy. He has reached the following conclusions : 
1. The acidity of the gastric juice, whether pure or 
mixed with food, is equivalent to 1*7 grammes of 
hydrochloric acid to a thousand grammes of fluid. 2. 
Acidity increases slightly at the end of digestion, and 
is independent of the quantity of liquid contained in 
the stomach. Wine and alcohol increase, but cane- 
sugar diminishes it. 3. If acid or alkaline matters are 
introduced, the gastric juice tends to return to its 
normal acidity. 4. The mean duration of digestion is 
from three to four and a half hours or more. Food 
does not pass successively, but in masses. 5. Accord- 
ing to four analyses made by a modification of 
Schmidt's method, it was proved that free hydrochloric 
acid exists in the gastric juice. 6. It is possible to 
extract all the lactic acid contained in the stomach, and 
to prove that there is one part lactic acid to nine parts 
hydrochloric acid. 7. Following the method of Berthe- 



GASTRIC JUICE. 



247 



lot, that is, by agitation with anhydrous ether and 
deprived of alcohol, it can he shown that lactic acid is 
free in the gastric juice. 8. The question so long in 
controversy as to the nature of the free acid in the 
stomach seems, according to Pichet, almost solved, and 
it may be said that in every 1,000 grammes of gastric 
juice there are 1*53 grammes of hydrochloric acid and 
0*43 of lactic acid. 

Pepsin. — Observation has shown that if an infusion 
of the mucous membrane of the stomach be made, and 
the liquid acidified, it dissolves albuminoid substances 
as well as the gastric juice. The mucous membranes 
of the other organs do not possess this property. 

Wasman was the first to extract from the mucous 
membrane of the- stomach the active agent of this 
transformation. 

It is an albuminoid substance known by the names 
of pepsin, chymosin, and gasterase pepsin. The best 
method of preparing pepsin is that of Schmidt. 
Gastric juice is neutralized with lime-water, filtered, 
evaporated to the consistency of syrup, and precipitated 
with concentrated alcohol. The pepsin is re-dissolved 
in water, precipitated with lead acetate ; the precipitate 
is collected and decomposed by a current of hydrogen 
sulphide. The sulphur is separated by filtering, and 
the liquid containing pepsin is evaporated to dryness 
at a low temperature. The method by Bruecke we 
omit, as it appears to give a less pure product. 

Pepsin is a yellowish gummy substance, soluble in 
water. Dissolved in 50,000 — 60,000 parts of acidu- 



248 ANIMAL CHEMISTRY. 

lated water, it dissolves coagulated white of egg in six 
or eight hours. Alone it does not possess this dis- 
solving power. 

Heat does not coagulate pepsin, but destroys its 
digestive properties. 

The union of pepsin and an acid is necessary for diges- 
tion. The acids of the stomach have been replaced by 
most of the other acids, with success. Artificial diges- 
tion may be very easily produced with pepsin and an 
appropriate amount of acid, or better, with gastric 
juice itself. If the proportion of acid is too large the 
action is stopped. The most suitable temperature is 
38° to 40° ; the action is very slow at 50° and at 12° ; 
no action takes place at 100° or at 5°. 

Liquid albumen does not coagulate in the stomach, it 
is dissolved, and the solution is not coagulable by heat 
or acids. Coagulated albumen is converted into a soft, 
nacreous substance, then into a sort of pulp, which is 
gradually dissolved. According to some chemists, 
albumen is absorbed directly. 

Fibrin is more energetically attacked by this secre- 
tion than ordinary albumen, which seems to prove that 
fibrin is neutral, while the alkali of the albumen, by 
saturating the acidity of the gastric juice, retards its 
action. Fibrin of the blood is attacked more rapidly 
than that of the muscles. At first it swells, then 
changes into a grey powder, which is finally dissolved. 
Grluten is dissolved very readily. Liquid casein co- 
agulates, and afterwards dissolves in the same manner 
as coagulated albumen. 



GASTRIC JUICE. 249 

The name peptones is given to the products of the 
transformation of albuminoid substances by the action 
of gastric juice. J. Murk has lately observed the pre- 
sence in saliva of a peptone ferment (60-'7 6-1800). 

Peptones are soluble in water, coagulated by alcohol, 
lead acetate, mercury bichloride, and tannin. They 
differ from albumen, inasmuch as their solutions are 
not coagulable by heat; peptones obtained from 
osseous and gelatinous tissues are not precipitated by 
potassium ferrocyanide. 

According to Meissner, the gastric juice produces 
with albumen, at first, a substance, parapeptone, 
identical with syntonin, which afterwards forms various 
other peptones. 

Peptone (a) is precipitated by nitric acid, also by 
potassium ferrocyanide, acidified with acetic acid. 

Peptone (b) is precipitated by the latter of these 
reagents. 

Peptone (c) is precipitated by neither reagent. 

Hoppe-Seyler and Grautier doubt the existence of 
these peptones. 

The gastric juice does not dissolve all the nitrogenous 
substances of the food. A portion escapes its action, 
and is subsequently transformed in the intestines. It 
is generally admitted that gastric juice has no action 
on fatty substances. 

Starch is not affected by the gastric juice, but it 
seems to be substantiated that the saliva continues its 
action on these substances in presence of the gastric 
juice. (Bruecke, Gautier, Besanez. Ed. of 1878, p. 831.) 



250 ANIMAL CHEMISTRY. 

In catarrh of the stomach the mucous secretion is very 
abundant, and various organic acids are formed. 



LIVER. BILE. 

Besides bile there have been extracted from the liver 
glucose, a substance analogous to starch, called glycogene, 
fatty substances, and various nitrogenous products, 
viz., leucin, tyrosin, and xanthanin. 

The quantity of bile secreted is quite large, Gruinea- 
pigs secrete in twenty-four hours a quantity of bile 
amounting often to several times the weight of their 
liver. In order to extract it from these or other 
animals the gall bladder is emptied, or the biliary 
ducts are ligatured, and an opening made in them. 

The bile before entering the gall-bladder is odourless. 
On remaining in this vesicle it acquires a strong odour, 
a bitter taste, becomes concentrated, and forms a viscous 
greenish or brown liquid. Its density varies from 
1.025 to 1.033. 

Its normal reaction is slightly alkaline. It is co- 
agulated by acids ; the coagulum is formed of two 
acids, taurocholic and cholic, or glycocholic acids. 

Human bile contains from 9 to 18 per cent, of solid 
substances ; a less quantity is found in the bile of the 
ox and pig. More than half of this residue is formed 
of combinations of the acids just named, with different 
bases, though mainly with soda. 

The bile may therefore be regarded as essentially 
a saponaceous compound. The other solid constituents 



COMPOSITION OF BILE. 



251 



of the bile are — a neutral organic substance called 
cholesterin, a colouring matter, neutral fatty substances 
and salts ; urea is sometimes found in it. 

Strecker has extracted a base from bile which he calls 
cholin. This substance is identical with neurin, which 
has been extracted from the brain and yolk of egg. 
Its formula is C 5 H 15 N0 2 . 

COMPOSITION OF BILE. 

(Gorup-Besanez.) 



Water 

Fatty substances 

Salts of the biliary acids 

Fat . 

Cholesterin 

Mucus, colouring- matters 

Mineral salts 



Man of 49 
years, de- 
capitated. 



822.7 
177.3 
107.9 

47.3 

22 1 
10.8 



Woman of Man of 68 Child ° f • *f 
•29 years, de- years, killed, 5 ^ 7 /' G1< 



capitated. 



898.1 

lul.9 

56.5 

30.9 

14.5 
6.3 



by a fall. 



908.7 

91.3 
73.7 
17.6 



of an 
injury. 



828.1 
171.9 

148.0 

23.9 



ae ash of ox gall contains ; — 




Sodium chloride 


o • 


27.70 


Sodium phosphate , 


o • 


16.00 


Potassium „ 


e o 


7.50 


Calcium „ 


o • 


3.02 


Magnesium „ 


CI • 


1.52 


Ferric oxide 


o • 


1.52 


Silica . 


3 8 


0.36 



Small quantities of nitrogen have also been found, 



252 ANIMAL CHEMISTRY. 

and considerable proportions of carbon dioxide ; this 
last gas may be extracted by a mercury pump. 
Animal food augments the quantity of carbon 
dioxide. 

Acids of the Bile. — Human bile contains much 
more taurocholic than glycocholic acid. 

The former alone exists in the bile of the dog ; it 
abounds in the bile of serpents and fishes. Grlycocholic 
acid is wanting in carnivorous animals. Both exist 
abundantly in the bile of the ox. 

The bile of the pig contains special acids : hyoglyco- 
cholic acid, and taurohyocholalic acid. 

In order to obtain the two acids of the bile, neutral 
lead acetate is added to ox-gall, which precipitates the 
glycocholic acid as a lead salt. This compound is col- 
lected, washed, boiled with 85 per cent, alcohol, and the 
boiling liquid filtered. It is then exposed to a current 
of hydrogen sulphide while yet warm ; the lead sul- 
phide is thrown on a filter and washed until the liquid 
becomes turbid. The glycocholic acid precipitates out 
of the solution, and is purified with boiling water. 

The alkaline taurocholate is not precipitated by the 
lead acetate. To the first liquor lead subacetate is 
added until the precipitate takes on a fatty consistency ; 
this precipitate is collected, washed, and suspended in 
water. A current of hydrogen sulphide is passed 
through the water, the liquid filtered and evaporated. 
The taurocholic acid is deposited as a white powder. 

Gtlycooholic Acid, C 2g H 43 N0 6 , forms white needles 
moderately soluble in alcohol. One part is soluble in 



TAUROCHOLIC ACID. 253 

100 parts of boiling and 300 parts of cold water. 
"With alkalies and barium it forms soluble crystalline 
salts. 

Boiling alkaline solutions and dilute acids, separate 
it into cholalic acid and glycoeol by combining with 
water. 

C 26 H 43 N0 6 + H 2 = C 24 H 40 O 5 + C 2 H 6 N0 2 

Glycocholic acid. Water. Cholalic acid. Glycocol. 

On being boiled with concentrated hydrochloric acid 
or sulphuric acid, it furnishes the following products : 



Cholonic acid . 


. C 26 H 41 N0 5 


Cholo'idic . 


• C 24 H 38 4 


Dyslisin 


2 4-ri 36 (J3 



Taurocholic Acid, C 26 H 45 N0 7 S, has not yet been 
obtained crystalline. It dissolves in alcohol and water, 
imparting to these an acid reaction. It is partly 
destroyed by the evaporation of its aqueous solution. 
It combines with one molecule of water on being 
boiled with alkaline solutions, cholalic acid and taurin 
being formed. 



C 26 H 45 N0 7 S + H 2 = C 24 H 40 O 5 + C 2 H 7 N0 3 S 

Taurocholic acid. Cholalic acid. Taurin. 

The Bile Ferment. — "W. Epstein and J. Miiller 



254 ANIMAL CHEMISTRY. 

(60-1875-679) have lately investigated the influence 
of different substances upon the action of the ferment 
of the liver. Dilute aqueous solutions of carbolic 
acid (1 : 300) do not prevent the transformation of the 
glycogen into sugar if brought into contact with fresh, 
finely-chopped liver; yet this carbolic acid solution 
protects the liver from putrefaction for a long 
time. Five per cent, solutions of sodium chloride 
and sodium sulphate do not prevent or influence 
the transformation of the glycogen of the liver. 
Alkalies render the change slower, acids prevent it 
entirely ; even when very dilute they greatly retard 
it. The action of acids, however, is only tran- 
sitory ; on neutralizing them the action of the ferment 
at once begins. Whether carbon dioxide prevents 
fermentation or not, has not been ascertained with 
certainty. The supposition of Tiegel that the change 
of the glycogen of the liver into sugar is connected 
with the destruction of the blood -corpuscles was not 
confirmed by the experiments of Epstein and Mtiller. 
They prepared from liver — moistening it with carbolic 
acid, drying at 30°, extracting with glycerine, and 
precipitating with alcohol — a ferment peculiar to liver, 
which converts glycogen into sugar very rapidly and 
easily. 

Taurin, C 2 H 7 N0 3 S. — This substance may be pre- 
pared by boiling ox-gall with an excess of hydrochloric 
acid for several hours. Filter and add to the liquid 
five or six times its weight of boiling alcohol, and 
allow to cool slowly. The taurin, which is almost 



CHOLESTERIN. 255 

insoluble in alcohol, will separate out in colourless 
rhoniboidal prisms. 

Taurin has been produced artificially by Strecker, on 
heating isethionate of ammonia at 200°. This salt 
loses one molecule of water, and taurin remains. 




(C 2 H 4 ,S0 2 )" |-0 2 = H 2 + [(C 2 H 4 , S0 2 )", HO]' 1 

Hj 1N 

This substance is, therefore, an amide like glycocol. 

Taurin is found in the muscles of certain mollusks. 

Cholesterin. — C 26 H 44 0,H 2 0. — This substance is 
widely diffused in the animal organism. Biliary cal- 
culi are almost entirely formed of it ; it is found in 
the blood, yolk of eggs, spleen, mis, in various tumours, 
in the nerves and brain. It is easily extracted from 
biliary calculi, which are pulverized, suspended in alco- 
liol with animal charcoal, and the mixture brought to 
boiling ; after some time, the liquid is filtered. The 
cholesterin deposits on cooling. 

Berth elot has shown that cholesterin has been 
wrongly classed among the neutral fatty substances ; 
it is not saponifiable. He considers it a monatomic 
alcohol. 

C 26 H 43 ) n 

Hj u * 

He has prepared the ethers of cholesterin by the 
action of acids : — 



256 ANIMAL CHEMISTRY. 



Acetic ether q 2 |^ q! 0. 



This alcohol is dehydrated by anhydrous phosphoric 
acid, producing the carbo-hydride : — 



C 26 H 42 cholesterilene. 



Cholesterilene is colourless, odourless, and tasteless, 
crystallizable in brilliant rhomboidal tablets, fusible at 
145°, and volatile at 360°. Water does not dissolve it ; 
it is slightly soluble in cold alcohol, and quite soluble 
in boiling alcohol and ether. It is soluble in the 
taurochlorates. It turns the plane of polarization to 
the left. 

Heated with a few drops of nitric acid it becomes 
yellow, and this yellow substance, on being touched 
with a drop of ammonium hydrate, turns red. Sul- 
phuric acid colours cholesterin red ; if chloroform is 
added, a blood-red colour is obtained which, before 
disappearing, becomes successively violet, blue, and 
green. 

According to Flint, cholesterin is an excrementitious 
substance, which results from the disintegration of 
nervous tissue, as it is not found in the blood entering 
the brain, but is found in the blood of the veins which 
leave it. Also, though absent in muscular tissue, it 
is always found in the nerves. It is absorbed by the 
blood and eliminated by the liver, as it is abundant in 
the blood of the hepatic artery and the vena porta, 



COLOURING MATTERS OF THE BILE. 257 

while little or none is found in the blood of the sub- 
hepatic veins. During digestion it is changed into a 
substance called stercorin, and evacuated in this state ; 
also, when cholesterin is not discharged into the in- 
testines, a decrease in the production of stercorin is 
observed. The retention of cholesterin in the blood 
gives rise to the serious malady cholesteremia. 

Colouring Matters of the Bile. — The bile fur- 
nishes two colouring matters : one brown, called 
bilirubin, cholepyrrhin, or bilifalvin ; the other green, 
called biliverdin. 

Bilirubin, C 16 H 18 N 2 3 . — This substance may be pre- 
pared by agitating fresh bile with water, ether, and 
dilute hydrochloric acid, which do not dissolve it, then 
with chloroform ; the bilirubin dissolves, and is de- 
posited on evaporation in orange-red crystals. 

This body is dissolved by alkalies. It forms with 
lime a sort of lake, sometimes also found in the body 
(biliary pigment). 

This substance has been found not only in the liver, 
but also in the brain, in cases of haemorrhage, and in 
the placenta of dogs. 

Biliverdin, C 16 H 20 N 2 O 5 , appears to be a product of 
alteration of bilirubin. It is first formed in the putre- 
faction of bile, is then changed spontaneously into 
biliprasin, C 16 H 22 N 2 6 (?). 

Biliverdin may be prepared by allowing an alkaline 
solution to stand for a time in the open air ; this solu- 
tion is then precipitated with hydrochloric acid. Both 
colouring matters are precipitated in this manner, and 



258 ANIMAL CHEMISTRY. 

the biliverdin may be removed by treating the precipi- 
tate with alcohol, which dissolves this substance alone. 
Stoedler announces that he has extracted from bile 
two other colouring matters — bilifuscin and bilihumin. 
The former has been recently studied by Simony 
(111-73-181). 

Action of the Bile on Food. — The bile is not 
simply extracted from the blood by the liver, but is 
elaborated by it ; the biliary acids are not found in 
any other part of the body, and the blood, in passing 
through the liver, loses its fibrin and a portion of its 
albumen. It has also been proved that the bile is 
formed in the liver, by removing this organ from 
frogs ; when, after this operation, biliary acids were no 
longer found. Lehmann believes that the fibrin, wholly or 
in part, taken up by the liver, is transformed into glycogen. 

The bile neutralizes the gastric juice, yet this satu- 
ration is not complete ; the acids of the bile thus 
liberated have perhaps a certain utility in the intestines. 

The bile has no digestive action on amylaceous 
matters, but assists in the digestion of fatty substances. 
Messrs. Schmidt and Bidder have shown that dogs 
assimilate, per kilogramme and per hour, under ordi- 
nary conditions, 0.465 gramme of fat, while only 0.093 
gramme is absorbed when the bile has been removed 
through a fistula. The chyle of a dog fed with fat 
contains at least 3 per cent, of this matter ; if the 
action of the bile be prevented by a fistula, this quan- 
tity will fall below 1 per cent. 

On agitating bile with oil, it forms a rapid and 



ACTION OF THE BILE ON FOOD. 259 

persistent emulsion. Oils rise higher in a capillary 
tube when moistened with bile than when moistened 
with water. 

Bile has no action on albuminoid substances in their 
ordinary condition. It precipitates acid solutions of 
albuminoid matter, but an excess of bile re-dissolves 
these precipitates. It is therefore not impossible that 
the bile takes part in the digestion of the albuminoid 
substances, acidified but not absorbed in the stomach. 

Bile is found throughout the smaller intestines ; it 
attaches itself to their folds, and by its adhesive charac- 
ter retains the non-absorbed food, and facilitates the 
action of the intestinal fluids. 

Bile is not found in the large intestine, although we 
find there cholalic acid, taurin, and dislysin ; glycocol 
has not been found. The excrements contain also 
taurin, dislysin, and cholalic acid, but Hoppe-Seyler, 
by determining the amount of this latter acid in the 
excrements, has shown that the greater part disappears 
in the intestine. 

The bile appears to prevent putrefaction of the con- 
tents of the intestine. 

The bile, therefore, after what we have stated, would 
seem to be a secretion, and also an excretion. 

But little is known in regard to the formation of the 
immediate principles of the bile. We owe to Lehman 
an ingenious and probable hypothesis regarding the 
formation of the acids of the bile. 

According to his theory the fatty substances, espe- 
cially olein, play an important part in their produc- 



260 ANIMAL CHEMISTRY. 

tion. In fact, the cholalic acid, like oleic acid in 
contact with alkalies, is broken up into an acetate and 
palmitate. Also the blood in passing through the 
liver loses fat ; the amount of bile increases when the 
food is rich in fatty and nitrogenous substances, and 
the amount of fat increases as the bile diminishes and 
diminishes as the bile increases. 

The bases to which these acids are united are 
derived from the blood, for it has been proved that the 
blood contains less salts on leaving the liver than on 
entering it. 

The nitrogen of these acids, in the taurin and 
glycocol, is obtained from the albuminoid matters, as 
the blood, in passing through the liver, leaves behind a 
notable quantity of these substances. The sulphur of 
these products has the same origin. 

Bilirubin appears to have great analogy with 
hsematoidin, which results from the alteration of the 
colouring matter of the blood ; hence it would seem 
rational to admit that the colouring matter of the bile 
is derived from that of the blood, and that the haemo- 
globin is destroyed in the liver. This explains why no 
blood is found in the bile. 

The biliary secretion augments two or three hours 
after eating, and increases up to the thirteenth or 
fourteenth hour. Vegetable food produces bile in less 
quantity and less concentrated than animal food. 

Fatty aliments, mixed with nitrogenous substances, 
increase both the amount of the bile and its richness in 
solids. 



PANCREATIC JUICE. 261 

The injection of calomel increases the secretion of 
bile. 

The biliary substances diminish in diabetes, in 
tuberculous affections, in dropsy, and typhus ; increase 
in choleric persons, and in diseases of the heart and 
abdomen. The biliary secretion diminishes in fevers. 

Biliary Calculi. — These are divided into biliary or 
cystic, hepatic, and hepato- cystic calculi, according to 
their origin. 

They are composed of cholesterin, mixed with the 
colouring matters of bile and mucus. Cholesterin forms 
80 per cent, of these calculi. To extract the 
cholesterin the powdered calculus is treated with 
boiling alcohol ; on cooling, beautiful nacreous blades of 
cholesterin separate out. 

Ox bile (gall) is employed for removing grease. It 
may be prevented from putrefying by evaporating to 
the consistency of syrup. 

We shall speak of glycogen under the head of 
nutrition. 

PANCREATIC JUICE. 

The pancreatic juice is a liquid, colourless and some- 
what viscous, having a saline taste. Its density is not 
uniform, as it contains variable proportions of solid 
matter, which have been found to amount to as high as 
11 per cent. 

Its reaction is alkaline, and due to sodium hydrate. 
The most important proximate principle of this juice is 



262 ANIMAL CHEMISTRY. 

an albuminoid substance called pancreatin. In it is 
likewise found a fatty substance, also leucin, tyrosin, 
xanthin, and several salts, among which are sulphates 
and chlorides. 

This juice owes to the pancreatin present its property 
of coagulating with heat, alcohol, and acids. This fact 
led to the belief, formerly, that the albuminoid principle 
of this juice was albumen ; this is not true, however, 
as the coagulum formed by alcohol re-dissolves in water 
and re-assumes the viscous appearance and the charac- 
teristics of pancreatic juice. 

Pancreatin is prepared by pouring 85 per cent, al- 
cohol into pancreatic juice. White flakes are formed, 
which are soluble in water, yielding a solution which 
possesses, to a high degree, the property of converting 
starch into sugar. Jenneret states (18-77-389) that 
the action does not require oxygen. 

Pancreatic concretions contain variable proportions 
of nitrogenous organic matter and calcium carbonate 
and phosphate. 

Action of Pancreatic Juice. — This juice appears 
to act upon the three classes of organic aliments ; it 
promptly forms an emulsion with neutral, fatty sub- 
stances, and is even capable of saponifying them. Its 
action is most rapid at about 35° ; its action is arrested 
by acids, even the acidity of the gastric juice retarding 
its action. It has been found, also, that in chyle 
neutral fatty substances predominate over acid fats, 
and it is therefore believed that the pancreatic juice 
renders fats assimilable by forming an emulsion witk 



ACTION OF PANCREATIC JUICE. 263 

them. The bile and intestinal secretion share with the 
pancreatic juice this property, for it has been shown 
that the chyle contains emulsions of fat, after the ligature 
of the pancreatic duct : their action, however, is very 
weak, as Bernard found that if the pancreatic juice be 
prevented from entering the intestines, the greater part 
of the fatty substances are found unchanged in the 
excrements. 

Corvisart, Kuhne, and others have shown that this 
juice dissolves fibrin and coagulates albumen, trans- 
forming them into assimilable products, analogous to 
the peptones. It, however, will act alone, whatever 
may be the state of the liquid, while pepsine requires 
the co-operation of an acid. According to Schiff the 
functions of the spleen are connected with those of the 
pancreas, as the pancreatic juice has no action on albu- 
minoid substances after the spleen has been removed. 

Moreover, and this, according to Bouchard at and 
Sandras, is its principal role, the pancreatic juice is the 
chief agent in effecting the transformation of farinaceous 
food. 

The transformation of starch into glucose is slow, as 
farinaceous mattex has been found in the intestines 
twenty-four hours after eating. It is probable that 
only a small quantity of the starch is absorbed in the 
form of glucose, the greater part being normally 
absorbed in the form of dextrine. The transformation 
continues, absorption having been accomplished, under 
the action of the ferment absorbed at the same time, 
with the dextrine. 



264 ANIMAL CHEMISTRY. 

Pancreatic juice is rapidly decomposed in contact 
with the air. 

Claude Bernard states that an infusion of pancreas, 
or a solution of pancreatic juice, after having stood in 
the air for some time, assumes an intense red colour on 
the addition of chlorine water. Nencki (18-'78-79) is 
of the opinion that pancreatic digestion is essentially a 
process of putrefaction. 



INTESTINAL FLUIDS. 

These liquids are complex products even when the 
ducts conducting the bile and pancreatic juice to the 
intestines are closed, as there are several varieties of 
glandular apparatus which secrete liquids throughout 
the length of the intestinal canal. Colin has shown 
that mucus is also secreted. This physiologist, by 
binding the intestine at two points, about two metres 
apart, was enabled to obtain about one hundred grammes 
of the liquid secreted by the glands of Lieberkuhn, and 
having removed the mucus by deposition and filtration, 
he examined its properties. 

It is a limpid liquid, slightly yellowish, secretion, 
whose density is 1.010 and reaction very alkaline. 
Saturated with an acid it is coagulated by heat. It is 
also coagulated by alcohol and precipitated by lead 
acetate. 

This fluid continues the transformation of farinaceous 
substances into dextrine and sugar, and forms emulsions 



INTESTINAL FLUIDS. 265 

with fatty matters. Although possessing an alkaline 
reaction, it acts upon albuminoid substances. Thus, 
according to Bidder and Schmidt, flesh and albumen 
coagulated by heat, and enclosed in the intestines by 
ligature, soften, dissolve, and are digested ; consequently, 
the intestinal fluid completes the digestion of nitro- 
genous substances : it is not known what constitutes its 
active principle. Thiry found in pure intestinal fluid 
from a dog : 



Water • 


. 97.585 


Albuminates .... 


0.802 


Other organic substances 


0.734 


Inorganic substances 


0.879 



The gases of the smaller intestines are chiefly carbon 
dioxide and hydrogen. In the larger intestine these 
gases are mingled with methane, and traces of hydrogen 
sulphide ; the methane amounts to as high as 50 per 
cent, of this volume when the food is vegetableo 

The excrements contain 10 to 15 per cent, of solid 
substance, of which 6 to 7 per cent, are mineral. In 
them has been found stercorin or serolin, which is 
a fatty non-saponifiable matter, a product of the 
decomposition of cholesterin, also a white crystalline 
substance, called excretin, which contains sulphur, and 
which probably effects the elimination of this element 
from the system. 

Calcareous and magnesian phosphates, sodium 



266 ANIMAL CHEMISTRY. 

chloride, a small quantity of silica, fatty matter, pro- 
ducts of the decomposition of the acids of the bile, of 
the epithelium, and the tissues of the vegetables are 
also found. 

The use of iron preparations colours the excrements 
blackish- green (iron sulphide). Calomel gives them 
a light green colour. If they contain blood the colour 
will be dark or nearly black. 

Cholera excrements contain coagulated albumen, 
cystoid corpuscles, and chlorides ; common salt amount- 
ing sometimes to over one-half the total weight. 
In dysentery and in Bright's disease mucus is found. 
In certain excrements the presence of alloxan, a pro- 
duct of the oxidation of urea, has been detected. In 
typhoid fever they are mostly fluid and alkaline. On 
standing a viscous mass deposits, containing mucus, food 
debris, and generally crystals of magnesio-ammonium 
phosphate. The fluid above the deposit contains 
albumen, various soluble salts and biliary constituents. 
Addition of nitric acid produces a rose-red coloration, 
as is also the case in cholera stools. 

Subjoined are the results of two analyses of human 
excrements, which from the inherent difficulties of such 
investigations cannot be regarded as exhibiting their 
composition with very complete accuracy. The one by 
Wehsarg is of recent date : — 



SUMMARY OF DIGESTION. 



267 







3erzelius 




Water 


• • 


75.30 




Biliary salts . 


. 0.90 






Mucus and biliary 


resins 14.00 






Albumen 


. 0.90 






Extractive matters 


. 5.70 






Aqueous extract 






5.340 


Alcoholic „ 






4.165 


Etherous „ 






3.070 


Food debris 


. 7.00 




8.300 


Mineral salts . 


. 1.20 






Earthy phosphates . 






1.095 


Total salts 




29.70 





Wehsarg. 

73.300 



21.970 



Intestinal Concretions. — These contain a large 
proportion of fatty matter, a substance analogous with 
fibrin, calcium phosphate, and sodium chloride. 

The name bezoar is given to the intestinal concretions 
found in gazelles and goats. They are formed some- 
times of an organic (lithiofellic) acid, sometimes of 
calcium and ammonio-magnesium phosphates. 



SUMMARY OF DIGESTION. 



To recapitulate, the food is mechanically divided in 
the mouth by the action of the tongue, teeth, and the 
saliva, which latter commences the transformation of 
the starchy matter. The bolus formed passes through 
the oesophagus, and arrives in the stomach, where the 



268 ANIMAL CHEMISTRY. 

digestion of the greater part of the nitrogenous sub- 
stances is effected by the action of the gastric juice. 
The majority of these substances having become 
assimilable, are absorbed by the walls of the stomach, 
and the remainder of the food passes into the duodenum. 
There the emulsion of the fatty matter is prepared, and 
the transformation of the starch into glucose effected 
by the action of the bile, pancreatic juice, etc. This 
latter ffuid also effects the digestion of the nitrogenous 
matters. 

The food as modified by these different changes 
forms chyme. It now enters the jejunum, and moves 
forward by peristaltic and muscular motions. It here 
receives the secretions, which complete the transforma- 
tion of starch into sugar, the solution of the albuminoid 
matter, and the emulsion of the fats. The chyliferous 
vessels absorb almost exclusively these latter substances, 
while the intestinal veins absorb the products of the 
transformation of the fluids and albuminoid bodies. 

The absorption of the liquid products of digestion, 
and, in general, the absorption of liquids, is effected by 
means of a very complex mechanism. 

Diffusion takes the principal part in this process ; in 
fact the animal membranes are lined with colloid cells, 
through which diffusion takes place with great 
rapidity, and we have seen that, although albuminoid 
substances are but slightly dialyzable in a natural state, 
they become quite readily so on being transformed into 
peptones. 



ABSORPTION. 269 



ABSORPTION. 

CHYLE, LYMPH. 

A very considerable quantity of lymph and chyle is 
constantly poured into the blood. These fluids are 
very analogous in character ; they have a circulatory 
movement; they are formed of a liquid (serum) in 
which float globules capable of uniting to form a clot or 
coagulum ; their composition is also similar, there being, 
in fact, little difference, except in the proportion of their 
elements. 

The chyle is a lactescent fluid contained in special 
lymphatic vessels, into which it passes directly from the 
intestines ; it accumulates in the mesenteric glands, 
whence it passes into the thoracic duct. It may be ob- 
tained by opening this duct and ligating the same near 
where it enters the sub-clavian vein. However, at this 
point it has already undergone elaboration, and is mingled 
with lymph coming from different points in the body. 
Before describing the chyle, it should be remarked that 
the knowledge we possess of this fluid is based chiefly 
upon investigations among the lower animals. 



270 ANIMAL CHEMISTRY. 

The chyle of an animal deprived of food is yel- 
lowish ; during digestion, especially of fatty food, it is 
lactescent. This appearance is due to the fatty bodies 
present, for if it be agitated with ether it loses its 
milky appearance. It has a feeble odour, a slight 
taste, and its reaction is faintly alkaline. 

Chyle contains fibrin, albumen, and urea. The pre- 
sence of casein" is suspected, but not certain ; yet the 
albumen of the chyle is more alkaline than ordinary 
albumen. The serum of chyle becomes covered with 
a film during evaporation ; it coagulates only in small 
flakes, and acetic acid precipitates it but partially. 
Chyle separated from the body coagulates in ten to 
fifteen minutes, producing a clot floating in an albu- 
minous liquid ; this coagulation is due to the fibrin 
present. 

Lymph is a colourless, or nearly colourless, liquid. 
It reaction is alkaline, which appears due, like the 
alkalinity of chyle, to a matter analogous with casein. 
It contains white globules, fibrin, albumen, urea, fatty 
bodies, and salts, which are chiefly lactates. 

It coagulates after being exposed to the air for a few 
minutes, producing a thin, soft clot, coloured red by 
globules of blood. 

Hobin found the composition of human lymph and 
chyle to be, in 1000 parts, as follows : — 



LYMPH, CHYLE. 


^71 




Lymph.. 


Chyle. 


"Water 


960 to 965 


900 to 990 


Sodium chloride 


4 „ 6 


5 „ 7 ^ 


Sodium carbonate 


1 „ 2 


not determined 


Calcium carbonate 






Alkaline and calcare- 


^0.05 „ 2 


0.80 to 3 


ous phosphates 






Alkaline sulphates . 


0.23 „ 0.50 


not determined 


Crystallized organic } 






principles (urea, r 


3 „ 8 


5 to 9 


glucose) . . ) 






Fatty bodies . 


2 „ 9 


10 „ 36 


Albumen . 


33 „ 60 


30 „ 40 


Fibrin 


1 „ 5 


3 „ 4 


Peptone . 


3 „ 4.5 


6 „ 8 


Hematosin 


0-6 


0.6 



Wurtz has found urea in the lymph of various 
animals. 

The above analyses do not wholly agree with those of 
other chemists, and from the variable character of these 
two fluids, and the inherent difficulty of their analysis, 
the foregoing figures must be considered as giving only 
an approximative idea of their chemical composition. 
The variations in composition are greater, however, in 
chyle than in lymph. 



272 ANIMAL CHEMISTRY. 



EESPIEATION. 



THE BLOOD. 



The blood is at once the nutritive and the purifying 
fluid of the body. From one part of the body it 
gathers the liquids elaborated by digestion, and in 
another it takes from the air its vital principle, oxygen, 
to act upon these liquids ; also it collects in different 
parts of the body the various effete products, and 
carries them to the organs destined to eliminate them. 
The blood also serves to distribute heat throughout the 
body. 

It circulates incessantly in the capillaries, arteries, 
and veins. Arterial blood is vermilion red; venous 
blood is reddish brown. Its odour varies somewhat 
with the species, and seems more marked in the male 
than in the female. According to Barruel, sulphuric 
acid increases its odour. 

Its taste is slightly saline. Its density varies be- 
tween 1.045 and 1.075. It has an alkaline reaction, 
which is due to sodium compounds. 

On placing under the microscope a very thin mem- 



THE BLOOD. 



273 



brane like the foot of a frog, it may be seen that the 
blood has a rapid circulatory movement, and that it is 
formed of a colourless liquid (plasma), in which floats an 
immense number of globules, drawn with it in the 
circulating current. The globules are microscopic in 
size, the majority are red, yet there are some which 
are colourless. 

A great many analyses of blood have been made. 
The results vary according to the physiological con- 
ditions of the subject, but the following tables give an 
average result: — 







Venous BloocL 






Man. 


Woman. 


"Water . • 




780.00 


791.00 


Grlobules 




140.00 


127.00 


Albumen 




69.00 


70.00 


Fibrin . 




2.20 


2.20 


Extractive matter 
salts . 


and ) 


6.80 


7.40 


Serolin . 




0.02 


0.02 


Fatty matters containing ) 
phosphorus . . jj 


0.49 


0.46 


Cholesterin . 




0.09 


0.07 


Salts of fatty acids 




1.00 


1.05 


Loss 




.40 


.80 



1000.00 1000.00 



274 ANIMAL CHEMISTRY. 

Salts contained in 1000 grammes of blood :- 



Sodium chloride 


. 3.10 


3.90 


Other soluble salts 


. 2.50 


2.90 


Iron o 


. 0.565 


0.541 


Phosphates 


. 0.330 


354 



(Becquerel and Rodier.) 

The blood on leaving the body loses its fluidity in 
a few minutes, becomes viscous, and changes into a 
gelatinous mass which gradually contracts and forces 
out drops of liquid, serum, which unite around the 
coagwlum or clot. This clot gains in consistency, and 
after ten to thirty hours it ceases to contract. 

Composition,, 
Serum . 870 

Clot ...... 130 



1000 



Each of the 'two parts composing the blood has the 
following composition : — 



THE BLOOD. 



275 



Clot 



i Fibrin . 
i Griobules. 
/Water . 

Albumen 

Oxygen . 

Nitrogen 

Carbon dioxide 

Extractive matter . 

Phosphorated fat . 

Cholesterin 

Serolin . 

Margaric acid. 

Sodium chloride 

Potassium chloride . 
Serum ( Ammonium chloride 

Sodium carbonate . 

Calcium carbonate . 

Magnesium carbonate 

Calcium phosphate . 

Sodium phosphate . 

Magnesium phosphate 

Potassium phosphate 

Sodium lactate 

Salts of fixed fatty acids 

Salts of volatile fatty acids 

Yellow colouring matter. 



ia?l 180 

790 

70 



> 10 



1000 
(Dumas). 



276 ANIMAL CHEMISTRY. 

Many other substances also exist in the blood. We 
may say, in a general way, that it contains most of the 
immediate principles which compose the tissues and 
liquids of the body. 

Coagulation of the Blood — Serum. — The blood, 
we have said, coagulates on being removed from the 
body. This coagulation seems to be due to the fibrin, 
for if the blood be beaten with twigs, the fibrin is seen 
to attach itself to the branches, and the blood has lost 
its property of coagulating. The serum of the coagulum 
is not therefore identical with the plasma. 

This latter contains fibrin, and the former has been 
freed of it. The fibrin imprisons the globules of the 
blood, and these together form the coagulum. 

Coagulation is net due to the fact that the blood 
remains at rest on leaving the body of the animal, or 
because it becomes cooled, for by keeping the blood in 
motion and maintaining the temperature of the body, 
solidification is not arrested. It is not due to the 
presence of air, as coagulation takes place in other 
gases and in a vacuum. Acids coagulate blood. The 
rapidity of coagulation varies from a few minutes 
to several hours. It is slower in the blood of the 
vigorous than in that of weak persons. It is accelerated 
by raising the temperature from 30° to 48°. 

It is retarded several hours by lowering the tempera- 
ture to 0°. The addition of albumen, sugar, and 
solution of alkaline salts produces the same effect, and 
coagulation is even arrested by concentrated solutions 
of certain salts, especially sodium sulphate. 

If pulverized sodium chloride be added to this liquid 



COAGULATION OF THE BLOOD — SERUM. 277 

it furnislies flakes of an albuminoid substance, which, 
according to Dennis, is different from albumen and 
fibrin. He has given it the name ofplasmin. 

It is very soluble in water, and is easily decomposed 
into soluble and insoluble fibrin, which, according to 
this chemist, is the cause of coagulation. 

Yirchow and Schmidt regard fibrin as produced by 

the combination of two albuminoid principles of the 

blood, the fib rino-plastic substance or paraglobullne and 

fibrinogen or metaglobuline, at the moment when the 

blood is removed from the body. 

These two bodies may be obtained by passing a 
current of carbon dioxide through plasma, diluted with 
ten times its volume of water at 0°. The fibrino- 
plastic substance is immediately precipitated in white 
flakes, which are collected on a filter and washed with 
water, charged with carbon dioxide, as aerated water 
dissolves it. The stream of carbon dioxide is now 
allowed to pass through the liquor for a long time. At 
first an abundant foam is formed, then the fibrogene 
separates out as a glutinous mass. 

If these two substances are separately dissolved in 
water which is slightly alkaline, and are then mixed, a 
gelatinous matter separates out which soon forms into 
filaments, analogous in appearance to fibrin. 

According to Schmidt these two substances require 
for their action the presence of a ferment, which is not 
developed in blood during circulation, but which is 
produced as soon as the blood is removed from the 
body; this ferment has not been isolated — whence 
is it derived ? 



278 ANIMAL CHEMISTRY. 

According to others, the fibrin is already formed and 
solid in the blood, and coagulation is simply the result 
of the aggregation of these solid particles. Supposing 
it to be proved that the fibrin exists in a solid state in 
the blood, it yet remains to determine the cause of this 
aggregation in air. 

It has been said that the fibrin surrounds or exists 
in the globules ; since, however, we can separate the 
globules and still have a coagulable plasma, this 
hypothesis is not admissible. 

Smee considers fibrin as oxidized albumen. But how 
can it be supposed that this oxidation takes place in a 
few seconds ? 

Notwithstanding all that has been written concerning 
the probable cause of the coagulation of the blood, it 
must be confessed that the causes thus far assigned are 
not wholly satisfactory. They are, for the most part, 
mere hypotheses. 

Serum is chiefly a solution of albumen. But this 
albumen is found in different states, free and combined 
with soda ; also, in the analyses above cited, the albu- 
minoid substances (fibrogene and fibrino- plastic sub- 
stance,) which are precipitated by carbon dioxide, have 
been considered as albumen. 

E. Mathieu and Y. Urbain (9-79, 665 and 698) 
seem to have established, though disputed by A. 
Grautier (9-83-277), that the coagulation of blood is 
caused by the carbon dioxide, which, when blood is 
exposed to the air, is expelled from the blood globules, 
in which it is contained during life, by the oxygen of 



SERUM. 279 

the air. Hence it is clear why alkalies and ammonium 
hydrate, as well as concentrated solutions of certain 
salts which absorb carbon dioxide, prevent the coagu- 
lation of blood. 

Yenous serum contains somewhat more water than 
that of the arteries, the serum of women containing, 
according to C. Schmidt, more water than that of men. 
The proportion of water increases in most diseases ; 
the reverse is seldom observed except in certain fevers 
and in cholera. 

The abundance of albumen in the serum and in the 
blood in general proves that this substance is the prin- 
cipal constituent of the albuminoid fluids and nitro- 
genous tissues of the body. Its proportion ranges 
between 63 and 70 in 1000 parts ; it increases at the 
moment of digestion. Yenous blood contains more 
albumen than arterial blood. Its quantity generally 
diminishes in disease ; yet it increases, as does the 
fibrin from other causes, in inflammatory fevers. 

The fatty bodies of the serum are often crystallizable, 
and it was a mixture of these substances which was 
formerly called seroline. There is a small quantity of 
olein and oleic acid in the serum. There is also 
found in it stearin, margarin, the two corresponding 
acids, and cholesterin. The venous blood contains more 
of this last body than the arterial blood ; the blood of 
the vena porta contains more than that of any other 
vessel. 

The amount of fatty bodies increases during diges- 
tion. They diminish in general during disease, with 



280 ANIMAL CHEMISTRY. 

the exception of cholesterin, which often increases. 
The blood of women contains a little more than that 
of men. 

Griucose always exists in the serum ; its proportion is 
very small ; it increases during digestion if the food is 
very starchy. The blood of the hepatic veins contains 
a considerable proportion of this substance, while the 
blood of the vena porta hardly contains any whatever. 
The blood of diabetic persons scarcely furnishes 0.05 
per cent ; normal blood contains at the most 0.0020 
per cent. 

The blood which is most rich in salts is that of the 
vena porta ; arterial blood in general contains more 
than venous blood. 

A considerable diminution in the quantity of 
sodium chloride in food affects health seriously. 

Many other substances have been found in the 
serum. Some are constantly met with ; these are 
urea, uric acid, hippuric acid, creatin, creatinin, casein, 
acetic acid, dextrin, and glucose, the peptones, sodium 
and potassium chlorides, sodium carbonate and phos- 
phate, sodium and potassium sulphates. Neither 
glycocol, leucin, taurin, nor tyrosin has been found. 

Prevost and Dumas detected the presence of urea 
in the blood after the suppression of the urinary 
secretion. The existence of this body in the blood 
has been proved by Bechamp and other experimenters. 
According to Picard, normal blood contains 0.017 
of urea ; twice as much is found in the renal artery 
as in the renal vein. 



THE COAGULTTM. 



281 



Casein exists principally in the blood of pregnant 
women, nurses, and nurslings. 

In leucocythsemia the blood contains gelatin, hypo- 
xanthin, lactic and formic acids : biliary acids in 
diseases of the liver, ammonium carbonate in persons 
having cholera. 

The coagulum — crassamentum or clot — is red and 
somewhat elastic. It is formed principally of fibrin 
and globules, and incloses about one-fifth of its 
volume of serum. It seems to form more rapidly in 
the blood of a child than in that of an adult, in 
that of women sooner than in that of men ; its com- 
pactness is in inverse proportion to the rapidity of 
its formation. 

In some pathological states the separation of the clot 
and serum does not take place, and a gelatinous mass 
remains. In others the blood is rich in fibrin, and a 
whitish matter called " buff," or buffy coat, is observed 
on the surface, which is fibrin nearly free from 
globules. 

On agitating coagulum in a bag placed in a stream 
of water the globules and other proximate principles, 
with the exception of the fibrin, are carried away by 
the water, and the latter remains in the cloth in the 
form of greyish filaments. 

Globules. —Blood globules may be obtained by 
receiving fresh blood in a saturated solution of sodium 
sulphate, then filtering ; the globules remain on the 
filter mingled with the solution of the salts. 

The red globules of the blood of mammalia are 



282 ANIMAL CHEMISTRY. 

minute circular disks, slightly thickened at the margin. 
It is generally admitted that they are formed of a 
colourless membrane ; they would, therefore, be verit- 
able cells. Yet some observers regard them as an 
agglomerated gelatinous substance destitute of exterior 
membrane. This latter view is not probable, for on 
placing a drop of blood on the slide of a microscope 
and adding a little water the globules are seen to 
swell, also the margins become yellow in contact with 
a solution of iodine. 

According to Bechamp and Estor, there exists in 
the blood on leaving the body an immense number 
of movable granulations of extreme minuteness, capable 
of development, of uniting and even of changing into 
bacteria and bacterides. These microscopic beings — 
called microcosms —are said to form the globules by 
their aggregation^?) 

These savants affirm that they have seen them form 
new cells, and that the blood- globules in the body are 
the result of the activity of the microcosms. The 
blood-globules in fishes, reptiles, and birds have an 
elliptic form. 

Milne-Edwards has shown that no connection exists 
between the size of animals and the size of their 
blood-globules, but that they are smaller as the organ- 
ism is more perfect and respiration more active 6 

Globules have a greater density than serum. Placed 
in contact with water they absorb the same, swell, and 
become spherical. At the same time a quantity of the 
colouring liquid of the globules is extravasated and 



GLOBULES. 283 

colours the water. Change of form exerts a great 
influence upon their colour. On swelling, they take 
on a darker tint. On losing water they become clear 
and red ; this takes place when they come in contact 
with sugar and alkaline liquids. The globules cannot, 
therefore, be collected on a filter and washed with 
water without becoming altered. A solution of sodium 
sulphate of 18° Baume does not attack them, and if a 
mixture of one volume of blood and two volumes of 
this solution be thrown upon a filter, they may be sepa- 
rated from the serum without being destroyed. 

This result is better obtained by adding to defibrinated 
blood ten times its volume of a concentrated solution of 
common salt ; the globules are precipitated, and may 
be washed with salt water. 

Besides red globules there exist in the blood white 
corpuscles ; their number is much smaller (about 1 in 
400). There appear to be two kinds. 

The most abundant, the plasmic, lymphatic, and 
fibrinous globules, have a spherical form. Their border 
is very well defined ; they contain a viscid matter in 
which float little nuclei, which refract light strongly. 
They are larger than the red globules (diameter =0.01 13 
millimetre), also lighter than these latter. 

They may be distinguished from the coloured 
globules by their different reactions. Water distends 
without destroying them, and dissolves them only after 
a long time. Acetic acid simply causes them to 
contract. 



284 ANIMAL CHEMISTRY. 

These globules are not, like the preceding ones, 
specially characteristic of the blood, for thej are found 
in most of the other fluids of the system. 

The name gtobulines has been given to certain white 
corpuscles, not numerous, whose diameter is about -j-^- 
of a millimetre. They are small spherical nuclei, 
which are probably derived from the chyle. 

The number of globules in a cubic millimetre of 
blood has been estimated at four to* five millions. 



ANALYSIS OF DKIED GLOBULES. 





Human Blood of a 




blood. dog. 


Haemoglobin 


. 86.79 86.50 


Albuminoid -matter 


. 12.24 12.55 


Lecithin 


0.72 . 0.59 


Cholesterin . 


.25 0.36 




(Hoppe-Seyler) 



The albuminoid matters appear to be constituted 
chiefly, if not wholly, of fibrino-plastic substance. 

Bed globules treated with water become spherical 
and distended, the colouring matter and other elements 
pass into the water, and there remains a gelatinous 
mass of a pale tint called stroma, which is formed 
chiefly of albuminoid substances. 

Haemoglobin. — This substance is prepared by 
mixing defibrinated blood with an equal volume of 



HAEMOGLOBIN. 285 

water, and adding to this liquid one-fourth its volume 
of 80 per cent, alcohol ; this mixture is allowed to stand 
twenty-four hours exposed to a temperature of 0°. 

Crystals then form in the liquid, which are pressed 
out on a filter and purified by re-dissolving in water and 
re-precipitating by adding to the solution one-fourth 
its volume of alcohol and exposing to a temperature 
below 0°. 

It may be easily obtained in an impure state by 
adding ether, drop by drop, to defibrinated blood. The 
colour of the blood darkens on account of the destruc- 
tion of the globules, and the liquid deposits crystals on 
exposure to a low temperature. This substance is also 
known as hcematocrystallin. 

The haemoglobin of human blood forms regular rec- 
tangular prisms ; the same is true of that of the dog, cat, 
horse, and lion. That of guinea-pigs and mice crystal- 
lizes in tetrahedrons, and that of squirrels in hexagons. 

It is insoluble in absolute alcohol, ether, chloroform, 
carbon bisulphide, and essential oils. Acids decompose 
it without dissolving. Alkalies dissolve it by altering 
its nature. It has a slightly acid reaction. It may be 
preserved after having been dried at a low temperature. 
In aqueous solutions it is slowly destroyed at ordinary 
temperatures, and instantly at 100°. It absorbs oxygen 
at ordinary temperatures, one gramme of haemoglobin 
dried at 0° absorbing more than 1 c.c. In a vacuum 
nearly the whole of this gas again escapes. Haemoglobin 
may therefore be considered as that constituent of the 
globules which fixes oxygen. 

E 



286 ANIMAL CHEMISTRY. 

Haemoglobin contains, besides carbon, hydrogen, 
oxygen, and nitrogen, small quantities of sulphur and 
phosphorus, and about 0.5 per cent, of iron. 

Haematin — H^emin. — An aqueous solution of haemo- 
globin heated to about 75° or 80° is decomposed into 
another colouring matter, haematin, and an albuminoid 
matter which coagulates. This decomposition takes 
place gradually at ordinary temperatures, in presence 
of acids or alkalies in solution. Haematin represents 
only about four per cent, by weight of haemoglobin. 

If a small quantity of sodium chloride and strong 
acetic acid is added to haemoglobin or blood, and after 
having heated this mixture over a water-bath, it is 
allowed to slowly cool, hydrochlorate of haematin 
(haemin) is precipitated in rhomboidal crystals of a brown 
colour ; this is also a characteristic test in medico-legal 
investigations. Yirchow, also Robin, have designated 
as hcematoidin a crystalline matter, containing neither 
iron, sulphur, nor phosphorus, and which results from 
the destruction of haematin in sanguinary effusions. 
This body is, however, now generally recognized as 
bilirubin. 

Haemoglobin forms with carbonic oxide a crystalline 
compound, which may be prepared in the same manner 
as haemoglobin, by employing blood previously 
agitated with carbon oxide. These crystals have the 
same form as the haemoglobulin. 

F. Hoppe-Seyler (60-1874-1065) has lately care- 
fully investigated the colouring matter prepared from 
haematin, by reducing substances, and proved its 



IRON IN THE BLOOD. 287 

identity with the urobilin of Jaffe (36-1869-815), and 
the hydrobiliruUn of Maly (36-1872-836). 

It should be observed that Thudichum and Kingzett 
have quite recently (32-' 76-255) made an analysis of 
hsemin, and finding the same to contain 7.65 per cent, 
iron, 3.02 chlorine, and 0.60 phosphorus, have come 
to the conclusion that haemin is in reality a substance 
consisting of hsematin, chlorhydrate of hsematin, and a 
crystalline compound containing phosphorus, which 
they regard as identical with myelin, a body claimed by 
Virchow as existing in the brain. 

C. Husson (9-81-477) states that crystalline com- 
pounds may be formed between hsematin and phenol, 
oxalic acid, valerianic acid, tartaric acid, citric acid, and 
silica. 

Haemoglobin forms crystalline compounds with 
nitrogen dioxide and cyanhydric acid. 

Eed globules are not attacked by albumen, gum, or 
sugar solutions, carbon dioxide, or neutral salts of the 
alkaline metals. Alum, chlorine, sulphuric acid, and 
nitric acid cause them to contract ; water, organic, and 
phosphoric acids, and alkaline solutions dissolve them. 

Milne-Edwards (9-79-1 268) remarks that the respira- 
tory power of the blood depends upon the number of 
red blood- corpuscles present. 

Iron in the Blood. — Boussingault determined this 
metal among the elements of cow's blood. In 100 
parts he obtained : 



288 ANIMAL CHEMISTRY. 

Total Mineral 
Substances. Iron. 

Dry fibrin . 2.151 grammes 0.0466 grammes 

Dry albumen . 8.715 „ 0.0863 „ 

Dry globules . 1.325 „ 0.3500 „ 

The colouring matter of tbe blood owes its colour 
mainly to tbe large proportion of iron in the globules, 
which, dried, gives : 

10.750 per cent, ash, containing 
9.043 „ ferric oxide, 
1.707 „ other mineral substances, 

formed almost entirely of lime and phosphoric acid. 

P. Picard (9-79-1266) found the proportion of 
iron in the blood of dogs to be quite variable and pro- 
portional to the amount of oxygen the blood was 
capable of absorbing. In his investigations regarding 
the amount of iron in the human body, the spleen gave 
higher proportions than any other organ. 

Jolly has very lately (61 -'78) made analyses that 
appear to show that the iron in blood exists as ferrous 
phosphate. 

GASES OF THE BLOOD. 

Magnus was the first to make, in 1837, an extended 
study of the gases contained in the blood. A flask con- 
taining blood was agitated violently, in order to coagu- 
late the fibrin. The defibrinated blood was transferred 



GASES OF THE BLOOD. 289 

into a bell glass, filled with mercury. He obtained 
the following composition of the gases liberated : — 



Venous Blood. Arterial Blood. 



Carbon dioxide 
Oxygen . 
Nitrogen 



71.6 


62.3 


15.3 


23.2 


13.1 


14.5 



100.0 100.0 



His methods of collecting the mixed gases were not, 
however, complete, and later analyses may be regarded 
as more reliable. 

C. Bernard determined the amount of oxygen in the 
blood, profiting from a fact discovered by him that 
carbon oxide displaces the oxygen. The blood is taken 
directly from the body by a syringe, and immediately 
introduced into a graduated tube half-filled with 
carbon oxide. This is agitated, and kept at a tem- 
perature of 40°, after which the amount of oxygen in 
the gas is determined. 

Yenous and arterial blood dissolve variable quanti- 
ties of oxygen. 100 volumes of blood from a young 
dog contained : 

In the left ventricle, 23.0 vol. of oxygen. Animal 

fasting. 
In the left ventricle, 17.6 vol. of oxygen. Animal 

digesting. 
In the right ventricle, 10.0 vol. of oxygen. Animal 

fasting. 



290 



ANIMAL CHEMISTRY. 



In the right ventricle, 10.2 vol. of oxygen, 
digesting. 



Animal 



The gases from the 


blood 


of a dog 


gave, in 100 


parts : 








Nitrogen. 


Oxygen, 


, Carbon 


Carbon di- 






dioxide. 


oxide combined. 


Arterial rl.61 
blood 12.30 


20.05 


34.8 


traces. 


22.2 


35.3 


0.88 


Venous rl.32 


12.1 


43.5 


4.40 


blood 11.64 


11.6 


42.8 


5.30 



When venous blood is agitated with oxygen it takes 
on the red colour of arterial blood. ? If, on the contrary, 
arterial blood be agitated with carbon dioxide, hydrogen, 
or nitrogen, it assumes the dark brown tint of venous 
blood. 

P. Bert (9-80-733) found, in his investigations upon 
the power of blood to absorb oxygen at different pres- 
sures, that a compound of haemoglobin with oxygen 
(oxyhemoglobin,) is obtained when blood is agitated 
with air at ordinary pressure. Increase of pressure in- 
creases the proportion of oxygen in this compound ; it 
also remains constant until the pressure is lowered to 
one-eighth of an atmosphere at 16°, but at the tem- 
perature of the bodies of mammalia it decomposes as 
the pressure is further removed. 

The blood on leaving the lungs does not contain as 
much oxygen as it is capable of absorbing. Grrehant 
has found that in agitating blood with oxygen the 
quantity which it is capable of absorbing is to the 



ACTION OF OZONE ON THE BLOOD. 291 

quantity ordinarily found in it as about 26 to 16. But 
there is a great difference in this regard between indi- 
viduals, their state of health, etc. 

The opinion has been expressed that the blood con- 
tains ozone, but this cannot be admitted, as the blood, 
like all organic matter, destroys ozone. It is only 
necessary to agitate blood in a vessel with ozone to 
obtain proof that these two bodies are incompatible, 
for the odour of ozone disappears immediately. 

J. Dogiel (75-24-431) states, as the result of his 
recent researches regarding the action of ozone upon 
the blood, that the action of the ozone is chiefly upon 
the red blood-corpuscles; their colouring matter is 
expelled, and they become darker within fifteen minutes. 
After this change alcohol, ether, or chloroform pro- 
duces no separation of crystals of haemoglobin. Upon 
passing ozone through defibrinated blood for a long 
time, flakes separate out, which, after washing with 
water, are not to be distinguished from fibrin. By 
continued action of ozone blood becomes first of a dirty, 
yellowish-green colour, and, finally, colourless. Hsema- 
tin is likewise rendered colourless by ozone. Blood 
poisoned with carbon oxide attains in a short time the 
properties of normal blood on exposure to the action of 
ozone, carbon dioxide being given off. Blood contain- 
ing carbon oxide is discoloured less quickly than 
normal blood, and does not so quickly lose its property 
of depositing crystals of haemoglobin. The change of 
the blood corpuscles produced by ozone should not be 
confounded with the change produced by carbon dioxide. 



292 ANIMAL CHEMISTRY. 

Carbon oxide displaces the oxygen of the blood, 
and is very deleterious when inhaled. 

Chlorine coagulates blood, removes the iron which 
enters into the composition of its colouring matter, and 
subsequently destroys the organic matter. The iron is 
changed into ferric chloride, capable of being detected 
with reagents. 

Arsenide of hydrogen completely changes the nature 
of blood, which assumes the colour of ochre. 

Defibrinated blood becomes brown and then dark 
green under the action of hydrogen sulphide; the 
colouring matter is attacked and the globules de- 
stroyed. 

Certain neutral salts, the alkaline sulphates, phos- 
phates, and nitrates, redden the blood in the same 
manner as oxygen. 

Ore (9-31-833, 990) asserts that acetic acid, sul- 
phuric acid, nitric acid, hydrochloric acid, phosphoric 
acid, or alcohol after being diluted with water, may be 
injected into the blood-vessels of a living animal with- 
out producing coagulation of the blood. 



DIFFERENCES BETWEEN ARTERIAL AND VENOUS 
BLOOD. 

We have incidentally noticed these differences in 
studying the various constituents of the blood. 
Longet sums them up as follows : 



INDUSTRIAL USES OF BLOOD. 



293 



Arterial Blood. 
1st. Vermilion red. 
2nd. Rich in fibrin. 
3rd. „ „ globules. ? 



4th. 

5th. 



6th. 
7th. 

8th. 



, , , , SclltS. 

Contains about 30 
parts of oxygen to 100 
of carbon dioxide. 
More coagulable. 
Less abundant in 
fatty matters. ? 
Has the same com- 
position in all parts 
of the arterial system. 



4th. 



5th. 



6th. 
7th. 

8th. 



Venous Blood. 
1st. Brown red. 
2nd. Rich in albumen. ? 
3rd. Has less water. 

„ „ extractive 
matters. 

Contains about 22 
parts of oxygen to 
100 of carbon dioxide. 
Less coagulable. 
Grlobules more abun- 
dant in fatty matter. ? 
Has a different com- 
position in different 
parts of the venal 
system. 
We have indicated by ? such items in Longet's tabula- 
tion as are doubtful, or at least are not constant. 

Industrial Uses of Blood.— Coagulated blood 
serves as food in certain countries, as Grermany, Sweden, 
and Italy. Freshly drawn blood is highly nutritious, 
and not unfrequently used by emaciated and greatly 
enfeebled invalids. The large quantity of albumen 
contained in the blood and the property which albumen 
possesses of coagulating on heating, causes blood to be 
employed in sugar refineries for the clarification of 



294 ANIMAL CHEMISTRY. 



CHEMICAL PATHOLOGY OF THE BLOOD. 

Since the blood circulates throughout the entire 
body, it is evident that diseases which manifest them- 
selves at any point necessarily produce modifications in 
the blood, hence it may be asserted that an examina- 
tion of the blood furnishes a valuable basis of dia- 
gnosis. Yet, from the fact that only blood taken from 
a superficial vein can be experimented with, and that 
the blood becomes contaminated in its passage through 
the body, the small quantity, therefore, of abnormal or 
noxious matter is often found to be too slight for the 
determination of its amount, or in some cases even for 
its detection. 

The chemical facts which we possess in regard to the 
variations of the blood in different diseases are few. It 
is only known that in such and such states there is a 
diminution or increase of this or that principle. We are 
not sufficiently informed as to the genesis of these 
substances to be able to decide, whether the morbid 
condition appertains to one organ rather than to an- 
other, or whether the disease is due to a given cause or 
to some other. 

The proximate principles of the blood may also 
seem to increase, without this increase being either 
real or as great as would appear ; this may be due to 
a diminution in the total mass of blood. 



ANOSMIA. 295 

Plethora. — Plethora may be due either to an 
increase in the proportion of globules, or an augmenta- 
tion in the volume of the blood ; therefore we distin- 
guish between globular and sanguinary plethora. 

In the former the globules increase. 

In sanguinary plethora — that is, in the augmentation 
of the mass of the blood — the reverse occurs, as the 
quantity of blood may increase in greater proportion 
than the globules. 

Anosmia. — Here also there may be either diminution 
of the mass of the globules or a diminution in the total 
amount of the blood. 

In the first case, an increase of water and fibrin is 
noticed in the blood, and often the number of colourless 
globules increases. The clot is firm and often produces 
« buff." 

The anaemic state occurs when the body does not 
repair the losses which it has undergone ; it is pro- 
duced during growth, at the time of puberty, or after 
diseases which impede digestion. Iron and its prepa- 
rations have a very favourable influence on the develop- 
ment of globules. 

We have just stated that certain anaemic conditions 
correspond to an increase of colourless globules. The 
spleen then increases in size ; the blood which remains 
in the spleen is very rich in white globules, contain- 
ing 1 to 49 of the coloured globules. The blood of 
the splenic vein also contains large numbers of these 
globules. The coagulum of the blood of this vein is 



296 ANIMAL CHEMISTRY. 

but slightly compact ; the serum which separates there- 
from coagulates after a short time. 

The following hypothesis based upon these facts 
has been proposed: The spleen is an organ which 
destroys red globules, changing them into white 
globules which are carried along into the circulation 
and afterwards again transformed into red globules. 
These views are, however, not regarded as established. 

Leucocythjemia. — This name is given to a morbid 
state characterized by the abundance of white globules : 
the number of these may amount to one-fourth and 
more of the total number of globules. The blood is 
then milky, and often acid from the formation of acetic 
or lactic acid. 

Cholera — Typhoid. Fever. — The globules assume 
irregular forms, and unite together during cholera and 
typhus. In this latter disease, and in tuberculosis in 
its advanced stages, the blood loses its property of 
becoming red in contact with oxygen, since this gas 
no longer unites with the globules. The blood of 
typhus patients contains ammonium carbonate, pro- 
duced by the transformation of urea, and it is probably 
this compound which leads to the alteration of the 
globules, as the same phenomenon is observed when 
ammonia is introduced into the blood. 

Ammonia and many toxic agents attack the enve- 
lopes of the globules ; hence, whenever these substances 
are present in the blood, the globules become ruptured, 
and death ensues in the absence of prompt antidotes. 

The blood is thick, and resembles gooseberry jelly in 



DISEASES IN WHICH THE FIBRIN DIMINISHES. 297 

cholera ; globules, as well as albumen and extractive 
substances abound. The serum is deficient, is dense, 
and generally poor in salts, jet the potassa compounds 
and phosphates increase. As the urinary secretion is 
diminished or suppressed, the urea increases in the 
blood, and there is produced ammonium carbonate. 

Scurvy. — The change in the blood is quite marked 
in this morbid state. It is disorganized on account of 
the dissolution of the globules, and the diminution of 
albumen and salts. 

Albuminuria. — The blood does not seem to change 
in the amount of fibrin. The proportion of globules and 
albumen is greatly diminished. 

Dropsy. — The globules and albumen diminish, and 
the serum is extravasated. 

Inflammatory Diseases. — The fibrin increases in 
these affections, in pleurisy, pneumonia, and acute 
articular rheumatism. The proportion of this body, 
which, in normal blood, is 2 to 2.3, rises to 7.8 and 
even 9 parts in 1000. 

The fatty matters augment, and the albumen and 
globules diminish slightly. 

The blood is charged with carbon dioxide, which 
fact explains the retarding of the coagulation, as a 
large proportion of this gas prevents coagulation. 

Diseases in which the Fibrin Diminishes. — When 
food is insufficient, also in cases of syphilis, in prolonged 
suppuration, in typhoid fever, and in scurvy, the fibrin 
generally diminishes, or loses its property of coagulating. 

The coagulation of the blood is very slow in diseases 
of the respiratory organs, when the hematosis is incom- 



298 ANIMAL CHEMISTRY. 

plete, and after death by syncope. It does not occur in. 
the blood of persons asphyxiated, killed by lightning, 
or poisoned with cyanhydric acid, narcotics, hydrogen 
sulphide, or ammonia. Usually in a fatal* result there 
is a complete destruction of the globules. In this case, 
oxygen ceased to unite with the blood, and the serum 
becomes coloured. The blood of persons who have 
died from the bite of a serpent coagulates very 
rapidly. It should be remarked that a decrease in the 
amount of fibrin in the blood does not always occur in 
the cases as cited above, and, indeed, it is claimed by 
Gorup-Besanez (21-364) that in no disease whatever is 
there uniformly a diminution in the fibrin. 

Variation in the Albumen. — The blood becomes 
poor in albumen under a great many circumstances : after 
loss of blood, prolonged suppuration, in albuminuria and 
dropsy, in malarial fevers, in typhoid fever, and scurvy. 

The albumen seems to diminish in proportion as 
the fibrin increases. 

Variations in Alkalinity. — Normal blood is 
alkaline This alkalinity increases in typhoid and 
putrid fevers, which is probably due to the formation in 
the blood of ammonium carbonate from urea. 

The blood has been known to become acid after an 
abnormal production of lactic acid. The globules are 
then dissolved by this body, and death rapidly ensues. 

The alkalinity seems to diminish in inflammatory 
diseases. 

Variations in the Fatty Bodies. — The drinking 
of large quantities of fluids augments the proportion of 
the fatty bodies, and it seems certain that corpulent 



VARIATIONS IN SUGAR. 299 

persons would grow thin on diminishing the quantity 
of liquid which they imbibe. 

The fatty matters generally augment during affec- 
tions of the liver, in phlegmasia, Bright's disease, and 
in the first stage of some acute diseases. 

Z. Pupier (9-80-1146) has lately found by extended 
researches that the use of sodium bicarbonate or 
alkaline mineral waters tends to increase the number 
of red blood-corpuscles both in man and animals. 

Other Variations. — The extractive vnatters become 
abundant in puerperal fever and scurvy. 

Claude Bernard recently (9-83-407) set forth the 
following, based upon his investigations regarding the 
quantity of sugar in the blood. 

The sugar of the blood is soon decomposed on the 
removal of the latter from the body. After death the 
sugar also rapidly decomposes, even when retained \v 
the blood-vessels. The presence of sugar is independent 
of the nature of the food ; in the arteries it is uniform 
in quantity, while in the veins, except in the hepatic, 
though variable, it is yet less than in the arterial system . 

The amount of sugar increases in diabetes. 

To extract the sugar of the blood, the latter is first 
defibrinated. To the serum is ao'ded its triple volume 
of alcohol ; the coagulum is separated and washed with 
water containing an equal volume of alcohol. It is 
now evaporated to dryness, and the residue treated 
with alcohol, which dissolves the sugar. 

V. Eeltz (9-80-553, 1338) recently ascertained by 
his investigations upon the action of putrefying blood 
upon animals, that injection of the same into a vein of 



300 ANIMAL CHEMISTRY. 

an animal produced septicemia. The poisonous pro- 
perties of putrefied blood are not changed by passing 
air through the same, but are lessened by the action of 
pure oxygen. If the gases of the blood are removed 
with a pump and the blood allowed to remain in a 
vacuum for some time, it loses its poisonous properties. 
Feltz is of the opinion that the poisonous body is a 
gas. In all stages of putrefaction, even after being 
dried in the air, blood retains the property of produc- 
ing septicaemia. 

Uric acid'is sometimes observed to increase in the blood. 

The blood of icterical persons contains the colouring 
matter and other constituents of the bile. 

Urea accumulates in the blood when the kidneys 
perform their functions badly ; this condition is known 
by the name of urcemia. The urea which accumulates 
in the blood is partially decomposed, producing 
ammonium carbonate. 

Von Grorup Besanez (75-23-135) found in the blood 
of a man suffering with atrophy of the liver, besides 
the normal constituents, a body closely related to 
gluten, but very different in its optical properties, 
hypoxanthin in not inappreciable quantity, formic acid, 
and volatile fatty acids, rich in carbon, also a non- 
volatile strong organic acid, soluble in water, alcohol, 
and ether, which, however, is not lactic acid. Uric 
acid, xanthin, leucin, and tyrosin could not be found. 

The proportion of salts diminishes in intermittent 
fevers, scurvy, Bright's disease, dysentery, and typhoid 
states. It augments in intermittent fevers and cholera. 



RESPIRATION. 301 



EESPIEATION. 



The atmosphere penetrates certain special organs, 
which are the • lungs in man, branchia in fishes, and 
trachea in insects. There is thus established a continual 
exchange between the blood and the air, which is called 
respiration. 

The oxygen of the air coming in contact with the 
membranous walls of the respiratory organ, which are 
very thin and very permeable, traverses them aud 
penetrates the blood. It is not dissolved in the serum 
of this liquid, but it fastens itself upon the globules, 
and forms with their substance a very unstable combi- 
nation. Inversely, the carbon dioxide and aqueous 
vapour on reaching the lungs in the venous blood 
escape through the same membranes, and are exhaled 
into the atmosphere to be again shortly decomposed by 
the green portions of plants. 



302 ANIMAL CHEMISTRY. 



THEOEY OF BESPIKATION. 

Different methods have been employed for studying 
the phenomena of respiration. Lavoisier was the first 
to solve the problem; his method, which has since 
been perfected by Regnault and Eeiset, consists in 
placing the subject to be experimented upon in a known 
volume of oxygen, absorbing the carbon dioxide ex- 
haled and renewing the oxygen, in a continuous 
manner. 

A second method consists in placing the subject in a 
confined space and analyzing this air> determining the 
volume of gas exhaled at each expiration, counting the 
number of respirations made during a certain time, and 
analyzing the air exhaled during this time. 

By this method absolute results cannot be obtained, 
as nitrogen is also exhaled during respiration, and thus 
we have two unknown data : the weight of the nitrogen 
exhaled, and that of the oxygen consumed to form 
water. 

Boussingault made use of an indirect method, which 
consisted in feeding the animal in such a manner that 
its weight remained constant, also weighing and analyz- 
ing the food, as well as the excrements, and subtract- 
ing the weight of the latter from the former. 

It is clear that the difference between these two 
weights represents what had been lost by pulmonary 
and cutaneous respiration. 



THEORY OF RESPIRATION. 303 

Boussingault experimented on horses, cows, and 
doves. 

The quantity of oxygen consumed is proportional to 
the energy with which the vital functions are executed. 

Dumas, experimenting on himself, found that the 
absorption of oxygen was at the maximum 23 litres or 
33 grammes per hour, or about 800 grammes for 24 
hours ; 13 litres of carbon dioxide are produced ; the air 
expired contains 4 per cent, of this gas. 

Substantially, the amount of oxygen consumed varies 
between 20 and 25 litres per hour, or 29 to 36 grammes 
for an adult man in a state of repose. 

We are indebted to Scharling, Andral, and Gravarret, 
also to Pettenkolfer, Eegnault, and Eeiset for important 
researches on respiration. 

The apparatus of Scharling consists of a chamber of 
one cubic metre capacity, made absolutely tight by a 
covering of sized paper. The subject is placed in this 
for half an hour to one hour. The air enters the 
chamber through an orifice in the lower portion, and is 
drawn in by £ water aspirator. The products of respi- 
ration pass into a series of flasks, the first of which 
contains sulphuric acid, which retains the moisture, the 
remainder containing alkaline substances to absorb the 
carbon dioxide formed. 

Two important objections to this method may be 
stated. The air is not sufficiently renewed, and the 
chamber is too small. It results, therefore, that the air 
of the box becomes charged with carbon dioxide and 
aqueous vapour, and becomes elevated in temperature 



804 . ANIMAL CHEMISTRY. 

in an unnatural manner. These circumstances exert a 
deleterious influence upon respiration, and must neces- 
sarily bring about abnormal conditions. 

Scharling found that in the respiration of a man 34 
grammes or 17 to 18 litres of carbon dioxide are pro- 
per hour. 

Andra'l and Gavarret took special care not to effect 
any modification of the normal conditions of respiration. 

A mask of thin copper, the edges of which were 
furnished with a cushion of caoutchouc in order to 
prevent any escape of gas, is fixed firmly to the face of 
the subject, which it covers without binding. 

This mask is large enough to receive the product of 
an entire respiration, and opposite the eyes it is j)ierced 
with two orifices closed with glass. 

The air penetrates the mask by two tubes, which 
enter the mask at the height of the corners of the lips. 
The air expired does not pass out through these tubes, 
as they contain two little balls of elder-pith, which serve 
as valves. The air escapes through an opening situated 
opposite the mouth, and enters into three flasks, from 
which the air has been exhausted, and whose capacity 
is 140 litres. 

The chief difficulty consisted in regulating the open- 
ing of the cock which separates the flasks from the 
opening in the mask, in such a manner that respiration 
could take place easily, both for inspiration and expira- 
tion. 

The operation lasted from eight to thirteen minutes, 
and the gas collected was about 130 litres. 



THEORY OF RESPIRATION. 305 

The cock was closed, the air was permitted to cool in 
the flasks, and the pressure and temperature determined. 
Then these flasks were placed in connection with three 
others exhausted, but separated from the first by tubes 
arranged for absorbing moisture and carbon dioxide. 

The gas was made to pass through the tubes slowly 
by opening progressively the cocks, and when the gas 
ceased to pass through the tubes the pressure in the 
first flask was again measured, the difference giving the 
amount of air which escaped. The increase in weight 
of the tubes containing the alkaline solutions represents 
the amount of carbon dioxide in this air. 

The experimenters operated on 37 men and 26 women 
of various ages, with results which we will now state. 

The respiratory phenomena attain their maximum 
energy at about thirty years of age ; they increase up to 
this age, then decrease until death. From 20 to 30 
years the quantity of carbon dioxide exhaled is 18 to 
20 litres per hour. 

Respiration is more active in men than in women. 
The production of carbon dioxide is greater during 
digestion than when fasting ; the relation increases from 
24 to 33, and even more. At the age of puberty there 
is a great increase in the production of carbon dioxide 
in man. This increase is arrested in woman at the age 
when menstruation sets in, and returns during several 
years after the critical age. It likewise increases during 
gestation. 

Respiration is feebler during sleep, and, according to 
Scharling, the quantity of carbon dioxide produced 
during sleep is one-fourth less than when awake. 



306 



ANIMAL CHEMISTRY. 



Exhaled air contains aqueous vapour ; this fact was 
observed by the ancients, for, on breathing upon glass, 
or other polished surface, a condensation of droplets of 
water was observed. This water was considered as 
exclusively derived from that introduced into the body 
with the food. Lavoisier distinguished water of 
pulmonary transpiration, proceeding from the lungs, 
from the water of respiration formed by the combination 
of oxygen with hydrogen. 

According to Valentin, the weight of water exhaled 
from the lungs during 24 hours is, in the mean, 540 
grammes, whiie, according to Barral, it attains to nearly 
650 grammes. 

It seems certain that expired air removes from the 
body a small amount more of nitrogen than the air in- 
haled introduces. According to Edwards, animals absorb 
nitrogen from the air, and disengage a small quantity 
of the nitrogen of their own substance. The researches 
of Regnault and Reiset, however, have demonstrated 
that the nitrogen of the air is not ordinarily absorbed 
during respiration, and, consequently, does not assist 
in nutrition under normal conditions. 

Among other principal conclusions of their important 
investigation were the following : — 

1st. When warm-blooded animals are submitted to 
their habitual alimentary regimen, they always dis- 
engage nitrogen ; but the quantity of this gas is very 
small ; it never amounts to more than -^-^ of the weight 
of oxygen consumed, and is often less than t ±-q. 

2nd. When the animals are in a state of inanition 
they often absorb nitrogen, and the proportion varies 



THEORY OF RESPIRATION. 307 

between the same limits as that of the nitrogen exhaled 
in the case where they are subjected to their natural 
regimen. The absorption of nitrogen almost always 
occurs in starving birds, but very rarely in mammalia. 

3rd. The relation between the quantity of oxygen 
contained in the carbon dioxide and the total quantity 
of oxygen consumed seems to depend much more upon 
the nature of the food than upon the class to which the 
animal belongs. This proportion is greater when the 
animals are fed with grain, and in this case exceeds the 
normal or unity. When they are fed exclusively with 
meat, this proportion becomes less, and varies from 
0.62 to 0.80. 

With a diet of vegetables, the relation is in general 
intermediate between the two just given. 

4th. The relation between the oxygen contained in 
the carbon dioxide and the total oxygen consumed 
varies for the same animal from 0.62 to 1.04, according 
to the diet to which it is subjected. It is therefore far 
from being constant. 

5th. The quantities of oxygen consumed by the 
same animal in equal times vary much, according to 
the different periods of digestion, the amount of activity, 
and many other circumstances. With animals of the 
same species, and of the same weight, the consumption 
of oxygen is greater in young than in adults ; it is 
greater in lean healthy animals than in very fat ones. 

6th. Warm-blooded animals disengage by respiration 
small and almost indeterminable quantities of ammonia 
and sulphuretted gases. 



308 ANIMAL CHEMISTS,!. 

7th. The respiration of animals of different classes 
in an atmosphere containing two or three times as 
much oxygen as normal air presents no difference from 
that which takes place in our terrestrial atmosphere. 
The consumption of oxygen is the same ; the relation 
between the oxygen contained in the carbon dioxide 
and the total oxygen consumed undergoes no perceptible 
change ; the proportion of nitrogen gas exhaled is the 
same, and the animals do not seem to perceive that they 
are in an atmosphere different from the ordinary one. 

In the recent experiments of Bert, he observed that 
if an animal be exposed to the influence of pure oxygen 
under a pressure of four atmospheres, it gives signs of 
discomfort, which are followed by violent convulsions, 
and death ensues if the pressure be increased to five 
atmospheres. 

It is to the action of the oxygen and not to the 
increased pressure that these effects are to be attributed ; 
for if a swallow be exposed to air under a pressure of 
three atmospheres, and then nitrogen at twenty atmo- 
spheres admitted, the animal perishes, slowly asphyxi- 
ated, without convulsions. The convulsions also ensue 
if the oxygen under four atmospheres pressure be 
replaced with air under twenty atmospheres. The 
analysis of the gases of the blood shows that when 
death ensues the blood, instead of containing 18 to 
20 c.c. of oxygen in 100, as in ordinary conditions, 
contains 35 c.c. An unusual combustion does not take 
place, for the temperature of the animal seems to fall 
sensibly, or at least it does not increase. 



SUMMARY OF THE THEORY OF RESPIRATION. 309 

On the other hand, when the pressure of the air 
is diminished until death ensues, the bird perishes 
asphyxiated in the midst of a pure air hardly con- 
taining any carbon dioxide. Then -death takes place 
because the pressure of the oxygen is not sufficient to 
maintain in the blood the quantity necessary for pro- 
ducing vital phenomena. 

Thus an aeronaut would be able to mount without 
danger to much greater heights than have hitherto 
been reached if he would inhale oxygen when suffering 
from the rarefaction of air. 

On the other hand, divers would be able to work at 
great depths without danger if, instead of sending them 
pure air, a mixture of air and nitrogen of definite 
proportions were supplied. 



SUMMARY OF THE THEORY OF RESPIRATION. 

Priestley was cognizant of the fact that air and 
oxygen — which latter element he had just discovered — 
had the property of reddening venous blood, and that 
carbon dioxide turned arterial blood to a brown colour. 
But, misled by the phlogistic theory, he did not have 
the satisfaction of establishing the theory of respiration 
and combustion — an honour which belongs entirely to 
Lavoisier. 

This theory enabled the latter chemist to explain 
animal heat, and in 1789 he wrote the following: — 

" Respiration is simply a slow combustion of carbon 



310 ANIMAL CHEMISTRY. 

and hydrogen which is similar, on the whole, to that 
which takes place in the name of a candle. Animal 
organisms are thus true combustibles, as they are 
oxidized in respiration and consumed at the expense 
of the oxygen of the air." 

As to the part of the body in which the combustion 
took place, he did not claim to make any assertion. 

Lagrange was the first to state that combustion 
takes place in the capillaries, and since then many 
investigators have established, by experiment, the truth 
of this assertion. 

In order to show, however, that the change in the 
colour of the blood takes place in the lungs, we have 
only to observe the lungs of a frog after having, by 
appropriate dissection, exposed them to view. The 
transparency of the membranes admits of the difference 
in the colour of the blood being plainly seen before 
and after leaving the lungs. 

The air produces this change, for if, as was done by 
Bichat, a cock be adapted to the carotid artery of a 
dog, the blood, which is red, becomes black when air is 
prevented from entering the lungs by closing a cock 
placed in the trachea ; and the red colour returns as 
soon as air is allowed to enter. 

The fact, perfectly demonstrated above, in regard to 
the relative insufficiency of oxygen and the abundance 
of carbon dioxide in the venous blood as compared with 
arterial blood, proves indirectly that an absorption of 
oxygen and a production of carbon dioxide takes place 
in the capillaries situated between the arteries and 



THE BLOOD AND ATMOSPHERIC OXYGEN. 311 

veins. But Spallanzani, and especially W. Edwards, 
have directly proved this important fact. The latter 
removed the gases from the lungs of a frog by com- 
pressing them under mercury, and introduced the 
animal under a bell-glass filled with hydrogen over 
mercury. The frog breathed for quite a long time ; 
the analysis of the gases showed that they contained a 
volume of carbon dioxide much greater than that 
exhaled by the animal under ordinary conditions. 

Oxygen. — Oxygen is not merely dissolved by the 
blood. If such were the case, the blood of persons 
living in mountains would contain less than that of 
those who live in the lowlands. Nothing of this kind 
has been observed at Quito (2,908 metres above the 
level of the sea), at Potosi (4,166 metres), or at Deba 
(4,812 metres) ; in the latter place, the atmospheric 
pressure is scarcely half of that at the level of the sea, 
and consequently the blood should contain but half the 
amount of oxygen. On the other hand, Eegnault and 
Reiset have observed that the absorption of oxygen does 
not increase when animals respire an atmosphere con- 
taining two or three times as much oxygen as ordinary 
air. 

It is well known that the quantity of any gas dis- 
solved is directly proportional to the pressure which 
the gas sustains. 

On the other hand, the coefficient of solubility of 
oxygen in the blood at 15° is 0.0287, or very nearly 
that of oxygen in water ; and it is the same for serum. 
Hence it results that one litre of blood should dissolve 



312 ANIMAL CHEMISTRY. 

only ^- of oxygen, or 5.7 c.c., while the real amount 
contained in the blood is 92 to 95 c.c. (Fernet) . 

It is therefore probable, d priori, that oxygen forms 
a combination with one of the principles of the blood. 
This principle is not the serum ; for if the blood be 
defibrinated and the globules removed, the serum 
dissolves scarcely more oxygen than water. If, on the 
contrary, defibrinated blood containing the globules 
be agitated with oxygen, it absorbs much more oxygen 
than the serum deprived of globules. If the globules 
simply dissolved the oxygen, the proportion would 
increase as the temperature decreased ; but this is not 
the case. At 40° to 45° a maximum absorption is 
observed, and at a higher temperature the phenomena 
of oxidation take place. A combination is therefore 
produced, and it follows from what we have said above 
that the haemoglobin of the globules must be the agent 
which effects the combination with the oxygen. This 
combination is also extremely unstable, as the oxygen 
may be almost completely removed in a vacuum. 

The oxygen of the blood acquires an energetic 
oxidizing power, comparable to that of ozone, at a tem- 
perature where ordinary oxygen is inactive. In fact, 
essence of turpentine, to which a few globules of arterial 
blood are added, turns litmus at once blue, in the same 
manner as when agitated in the air in the sunlight. 
Hydrogen peroxide dissolves pyrogallic acid without 
becoming coloured; but if to this solution platinum 
black or blood globules be added the brown coloration 
is at once produced. 



THE BLOOD AND CARBON DIOXIDE. 313 

The blood contains, besides oxygen combined with 
the globules, a small proportion of this gas dissolved 
in the serum. 

It should be also stated in this connection that a 
small portion of the oxygen inhaled is employed to 
oxidize the sulphur of complex sulphur compounds, 
the albuminoids, etc. 

Carbon Dioxide. — Carbon dioxide is not, like 
oxygen, combined with the globules. Fernet has 
determined the quantity of this gas which the con- 
stituents of the serum — water, carbonate, phosphate, 
and chloride of sodium — are capable of absorbing, 
either by dissolving or combining with it ; and the 
result of these researches shows that the quantity of 
carbon dioxide found in the blood is very nearly equal 
to that which the serum alone absorbs. 

The quantity of carbon dioxide exhaled is less during 
sleep than when awake, for, as the organs are at rest, 
the oxidation is not then so great. 

The carbon dioxide is not derived from the atmo- 
sphere, since the gases exhaled contain more than the 
air, and its proportion, which is small in arterial blood, 
is observed to increase as this liquid traverses the 
organs in which the combustion takes place. This gas 
is therefore formed in the body, and is rejected as a 
waste product. 

F. M. Eaoult (9-82-1101) finds, as a result of recent 
experiments, that the presence of carbon dioxide in 
inhaled air causes a diminution of the carbon dioxide 
exhaled, and therefore in the oxygen consumed. 



314 ANIMAL CHEMISTRY. 



Nitrogen. — Nitrogen forms at the most one-tenth 
of the gases of the blood, which contains 2 to 3 per 
cent, of this gas, while the serum dissolves only 1 per 
cent. ; consequently there is for this gas a special action 
not as yet explained. 

To review, the vesicles of the lungs act as a porous 
membrane ; and this organ should be regarded as an 
apparatus for the exchange of gaseous bodies. 

The blood which has become red in the lungs 
retains this colour until it enters the capillaries. On 
leaving the capillaries it is darker, and instead of 
oxygen it contains carbon dioxide. Consequently it is 
in this transit that the combustion takes place. This 
combustion either occurs in the capillaries proper, or the 
oxygen traverses their dialyzing walls and penetrates 
into the depths of the tissues whence the carbon dioxide 
escapes. This latter hypothesis is more in favour than 
the first. There is an exchange of gases in the centre 
of these structures as in the lungs, and the oxygen 
coming from the air penetrates into the innermost parts 
of the body of animals, and there effects the oxidation 
of the tissues themselves. 



VARIATIONS IN THE GASES EXPIRED IN PATHOLOGICAL 

STATES. 

We have but little information on this point. 
According to Hervier and Saint-La^er " the proportion 
of carbon dioxide decreases in all diseases in which 



GASES EXHALED IN PATHOLOGICAL STATES. 315 

respiration is impeded, as in pulmonary phthisis, pneu- 
monia, pleurisy, pericarditis, eruptive fevers, and typhoid 
affections." 

In diabetes, chlorosis, anaemia, and in diseases in 
which there is no febrile movement, the variations in 
the proportion of carbon dioxide are hardly appre- 
ciable. In inflammations the carbon dioxide increases 
in a remarkable manner. 

Hayer, and afterwards Doyere, have affirmed that 
the air exhaled by cholera patients contains more 
oxygen and less carbon dioxide than the air normally 
expired. The quantity of oxygen absorbed is always 
greater than that of the carbon dioxide exhaled. 



316 ANIMAL CHEMISTRY. 



NUTRITION. 

Animals canno't live unless able to respire and 
obtain nourishment, i.e., to ingest matters which are 
digested, absorbed, transported to the blood and sub- 
mitted, subsequently, to the action of oxygen. 

The food, carried by the blood into the different 
organs, undergoes therein two different changes. One 
part is burned, as coal in the furnace, producing heat and 
physical energy. The remainder becomes organized to 
form the tissues, since an animal, considered even in an 
adult state, and at a period at which its weight does 
not vary, constantly fixes matter in its organism, and 
therefore also loses an equivalent amount. 



ANIMAL HEAT MUSCULAR POWER. 

These two subjects are intimately connected with one 
another, and with respiration. 

The temperature of animals, and even that of plants, 
is not uniformly that of the medium in which these 
beings live. It varies also with the species. In man it is 
very nearly 37 degrees, in whatever climate he may live. 



ANIMAL HEAT MUSCULAR POWER. 317 

The two extremes of temperature in which man can 
exist are very remote. He alone is capable of dwelling 
in all latitudes, in the most varied climates, and at 
heights so great that the pressure is only one -half of 
that at the level of the sea. 

Different portions of the body have not the same 
temperature. The exterior parts, from the cooling effect 
of the surrounding medium, are reduced in temperature 
4 to 5 degrees below that of the interior. The muscles 
are 1.5 to 2 degrees warmer than the cellular tissue. 

It is the blood which, traversing the whole body, 
tends to equalize the heat disengaged in the different 
organs. The liberation of gases in the lungs lowers 
their temperature slightly, and especially that of the 
left cavities as compared with the right. The venous 
blood in the extremities is slightly less warm than 
the arterial blood, but this is due to the external 
position of the vessels. 

The conditions which cause the activity of the 
respiration to vary, that is, the absorption of oxygen, 
produce also a corresponding variation in animal heat. 
The temperature of the body of an infant or an old 
man is less than that of an adult, and we have 
observed that the respiratory phenomena diminish in 
energy at the two extreme points of life. 

If an important reduction in temperature is pro- 
duced after eating, it must be attributed to the fact 
that the blood rushes to the muscles of the digestive 
apparatus, which act with increased energy at this 
time. 



318 ANIMAL CHEMISTRY. 

Like the fuel of an ordinary engine, a part heats 
the animal machine, the other is converted into mus- 
cular activity, which produces either external work 
(walking, movements of the arms, head, etc.), or in- 
ternal work (digestion, assimilation, etc.). Thus the 
observed heat is equal to the difference between the 
heat produced and the heat which is transformed into 
work. Now, since we know the mechanical equivalent 
of heat, that is, the quantity of work which a certain 
amount of heat will accomplish, the heat produced can 
be measured. 

If the muscle contracts without producing mechanical 
effect, the heat developed will be greater, since there is 
only heat developed, and that not utilized in the form 
of work. But even if the muscular power does produce 
an external mechanical effect, there is still in addition 
a production of heat in the interior of the body. Ex- 
periment has shown that when a muscle contracts the 
quantity of oxygen consumed is greater than when it 
is in repose: thus 100 volumes of blood, leaving a 
muscle which is in action, instead of furnishing 6 
volumes of oxygen, furnish only 2 volumes. 

All chemico-physiologists are in accord in admitting 
that heat and motion are due to the oxidation of the 
food. The amount of carbon dioxide exhaled does not 
indicate the amount of oxidation which has taken 
place in the body. Every movement, every chemical 
action, every passage of the food from a solid to a 
liquid state in the blood, all friction of the liquids 
in the body, are actions which go to produce an 



ANIMAL HEAT — MUSCULAR POWER. 319 

elevation or decrease of temperature. Consequently 
there are incessant gains and losses of heat, and we 
perceive, on the whole, only the resultant of these 
different actions of which the complexity is extreme. 

The carbon dioxide is not the only product of oxida- 
tion ; water and other matters (urea, uric acid, etc ) are 
formed, which escape in the different excretions. And 
the whole of the oxygen which oxidizes is not derived 
from the air ; a considerable part is obtained from the 
oxygen of the food itself. 

There is a difference of opinion as to the manner in 
which the action is produced. According to some, it 
results from the oxidation of the aliments as they are 
found in the blood. Others do not admit that the 
process takes place in the blood, but that it is a direct 
oxidation of the muscles by the oxygen which produces 
heat and motion. 

The second view is that most generally admitted ; 
nevertheless, the recent researches of Meyer and Frank- 
land on this subject appear to prove the contrary. 

An average man has about 7.5 kilos of muscles, 
considered in a dry state. According to Meyer, they 
would be completely oxidized in eighty days if they 
served to produce mechanical work. 

It is rational to regard the muscles as instruments 
for the transformation of potential energy into motion. 
We can only give a few conclusions deduced from the 
work of Frankland. 

1st. The muscle is a machine destined to convert 
potential energy into mechanical force. 



320 ANIMAL CHEMISTRY. 

2nd. The mechanical force of the muscles is derived 
principally, if not wholly, from the oxidation of the 
substances contained in the blood, and not from the 
oxidation of the muscles themselves. 

3rd. In man the principal substances employed in 
the production of muscular power are non-nitrogenous ; 
but nitrogenous substances may also be employed for 
the same object, hence the great increase in the evolu- 
tion of nitrogen under a diet of animal food, even with 
no increase in the amount of muscular work performed. 

4th. Like all other parts of the body> the muscles are 
constantly being renewed ; but this renewal is not 
apparently more rapid during great muscular activity 
than during comparative repose. 

5th. After a sufficient quantity of albuminous sub- 
stances has been digested for the renewal of the tissues, 
the best food for the production of work, both internal 
and external, are the non-nitrogenous substances, such 
as oil, fat, sugar, starch, gum, etc. 

6th. The non-nitrogenous portions of the food which 
enter into the blood transform all their potential energy 
into effective force ; the nitrogenous substances, on the 
contrary, leave the body, taking with them a part (one- 
seventh) of their potential force. 

7th. The transformation of dynamical force into 
muscular power is necessarily accompanied by a pro- 
duction of heat within the body, even when the 
muscular force is exerted exteriorly. This is, without 
doubt, the principal though not the only source of 
animal heat. 



TRANSFORMATION OF ALBUMINOID SUBSTANCES. 321 

Fick and Wislicenus, in an ascension of the Faulhorn 
in 1865, determined the amount of work performed by 
their muscles, and the quantity of muscular matter 
oxidized to produce this work. This latter calculation 
was made by determining the amount of nitrogenous 
matters in the urine emitted, and collecting them in the 
form of urea, and based upon the fact established by 
Frankland, that 1 gr. of dried muscle transformed into 
urea produces 4,368 heat units. They arrived at the 
result that the work accomplished was about twice as 
great as that which would be produced by the com- 
bustion of the substance of the muscles transformed 
into urea. 



TRANSFORMATION OF FOOT) JN THE BODY- 

We recognize three principal classes of food, albumi- 
noid, farinaceous, and fatty. 

Transformation of Albuminoid Substances. — It was 
formerly believed that albuminoid matters were not 
modified in the body, but simply fixed in the tissues, 
and taking no part in the respiratory phenomena. The 
name of plastic food given to these bodies illustrates 
perfectly this manner of regarding them. On the other 
hand, the fatty and farinaceous bodies were thought to 
take part in the production of the respiratory pheno- 
mena alone. Hence the name respiratory aliments, which 
has been given them. This view, however, is too limited ; 
carbon dioxide and water are the principal but not the 
only products exhaled. Others are formed, as urea, 
uric acid, and these substances are nitrogenous. There 



322 



AN1MAT, CHEMISTRY. 



escapes also in the gas exhaled by the lungs a certain 
quantity of free nitrogen. It is well known that the 
framework of animal tissues is nitrogenous ; but it is 
none the less certain that different tissues are filled 
with non-nitrogenous matters, such as the fat of adipose 
tissue and jlycogenous substances. 

The albuminoid matters undergo in the blood, and 
afterwards in the organs to which the blood carries 
them, numerous transformations, most frequently pro- 
duced by oxidation. To prove this it will only be 
sufficient to enumerate the different nitrogenous 
principles found in the body. These are mainly : — 



[ Urea 
I Uric acid 
Urine < Hippuric acid . 

Cystin . 
Xanthin . 
Perspiration — Sudoric acid . 

( Taurocholic acid 
Liver . . . ( Grlycocholic acid 
'v Cholesterin 
/ Leucin . 
Tyrosin . 
I Lactic acid 
( Creatin . 
Creatinin 
' Inosite . 
I Inosic acid 
I Sarcosin . 
Sarcin (Hypozanthinj 
-Ossein. 



Pancreas 



Muscles 



Osseous tiss 



0H 4 N 2 O 
C 5 H 4 N 4 3 

C 9 H Q N 4 3 

c 3 h;xso 2 

C 5 H 4 N 4 2 

C 10 H s O l5 X? 

C O6 H 4 ,X0 7 S 

C 96 H 43 N0 6 

C^H^O + HaO 

C 6 H 13 N0 2 

C 9 H n N0 3 

C 3 H 6 3 

C 4 H 9 N 3 2 

C 4 H 7 X 3 

C 6 H r A + 2H,0 

C 5 H 8 N 2 6 ? 

C 3 H 7 N0 2 

CLH 4 N 4 



sue- 



glucose in the liver. 323 

Transformation of Amylaceous or Farinaceous 
Food. — Starchy matters are only found in small 
quantities in the tissues of the body — a fact which is 
quite natural as regards carnivorous animals, but very 
surprising in the case of herbivorous animals; and 
which seems to prove that starch is the chief respiratory 
aliment, and that it is very easily oxidized or burned. 
The greater part of the starch is transformed into 
carbon dioxide and water. Another portion is con- 
verted into fat, and the rest (a minute fraction) is fixed 
in certain tissues. 

Glucose in the Liver. — The existence of amyla- 
ceous matter in animal tissue is connected with a 
remarkable discovery made in 1849 by the illustrious 
physiologist, Claude Bernard — a discovery which we 
shall now describe, as well as the researches which led 
to it. 

If a carnivorous animal be subjected to prolonged 
fasting, sugar will be found in the hepatic tissue. The 
proportion of sugar found in the liver of carnivorous 
animals, or of animals fed exclusively with meat, is 
substantially the same as that in the liver of herbivorous 
animals, or of animals fed with amylaceous or saccha- 
rine food. Hence the production of sugar does not 
depend upon the existence of amylaceous and saccha- 
rine substances in the food. 

Objections might be raised to such experiments, on 
the grounds that the blood, in passing through the liver, 
might leave sugar behind it in this organ, and that 
sugar is merely retained and accumulated by the liver. 



324 ANIMAL CHEMISTRY. 

Bernard responds to these suppositions by an experi- 
ment as interesting as it is conclusive. If a dog is killed 
and the liver removed, and, after washing this organ 
in such a manner as that all the su^ar shall be dissolved, 
it is allowed to remain exposed to the air for a day, 
it is found to again contain a very large proportion of 
sugar. 

If, also, the blood of the vena porta be analyzed 
before it reaches the liver, as well as after leaving this 
organ in the superior hepatic veins, a considerable 
increase in the amount of sugar is observed. In order 
to extract the sugar of the liver, the latter is cut into 
very small pieces and treated with boiling or even with 
cold water till nothing more is dissolved. The liquid 
is decoloured with animal charcoal, and evaporated 
over a water bath almost to dryness, and the residue 
treated with alcohol. The alcoholic solution furnishes 
glucose on evaporation. 

Bernard found 23.27 gr. of sugar in the liver, weigh- 
ing 1,300 grammes, of a hanged criminal of forty-three 
years, and 25.70 grammes in that of another, aged 
twenty-two, and whose liver weighed 1,200 grammes. 

Glycogene. — Sugar is produced in the hepatic tissues 
by means of a third substance — a sort of animal starch, 
designated glycogene — which has also been found on 
the internal surface of the amniotic membrane of 
ruminants, between the maternal and foetal placenta of 
rodents, in the muscles, and in the lungs of the foetus, 
and later in the liver ; also in different parts of the 
Crustacea and articulates. 



GLUCOSE IN THE LITER. 325 

To prepare glycogene, the liver of a dog recently 
killed is cut into very small pieces and thrown into 
boiling water to precipitate and destroy the ferment 
which would otherwise change the starch into sugar. 
The fragments are now withdrawn, triturated with 
animal charcoal, and the pulp obtained boiled for about 
twelve minutes with five times its weight of water, 
filtered, and the residue treated with additional water. 
A liquid is obtained, from which the glycogene may be 
precipitated by alcohol. 

Glycogene is a white powder, soluble in water, 
which it renders milky, and insoluble in alcohol. The 
solution turns the plane of polarization strongly to 
the right. It has the composition of starch, x (C 6 H 10 O 5 ), 
is coloured violet-red by iodine, is converted into 
pyroxam by fuming nitric acid, and furnishes dextrine 
and glucose under the same circumstances as vegetable 
starch. 

The transformation of glycogene into sugar is effected 
by means of a ferment »analogous to diastase, which is 
found in fresh liver and even in the blood. 

According to Pavy, the proportion of glycogene in 
the liver varies with the nutrition ; it is large if the 
food is vegetable, and is, on the contrary, small if the 
food is animal. 

Amount of Glycogene 
in the Liver. 
Dog fed with amylaceous food. 17.23 per cent. 
„ „ „ meat. . . 6.97 „ 
? , „ „ „ mixed with 

sugar .... ltL50 „ 



326 ANIMAL CHEMISTRY. 

Bouget arrived at analogous results. On the other 
hand, Sanson has announced that on giving animals 
very farinaceous food, dextrin is found in the hlood 
and even in the muscles ; consequently muscles sup- 
plied as food would furnish amylaceous matters directly. 
There also exists in the muscles a saccharine substance 
called inosite, C 6 H 12 6 , and lactic acid ; consequently a 
diet of meat forms in the body amylaceous products. 

Amylaceous matter is also found in the muscles of 
new-born mammalia, and in the muscles of an organ 
when in absolute repose for a certain time. This all 
leads to the belief that there is an amylaceous matter 
which takes part in the formation of muscular tissues, 
but which disappears under ordinary circumstances, and 
is transformed into inosite and lactic acid. 

From these facts, and the existence of glycogene in 
other parts of the body than the liver, it follows that 
the liver is not absolutely the only organ having the 
property of transforming starch into sugar, but that it 
possesses it in a much greater degree than do the 
others. 

The sugar thus formed in the liver then passes into 
the blood, and there disappears, under normal condi- 
tions, being burned by the oxygen ; but certain natural 
or artificial conditions may diminish or increase the 
formation of this sugar. 

If the spinal cord be dissevered below the phrenic 
nerves, the circulation becomes weaker in the abdominal 
region, the temperature is lowered, and sugar is no 
longer found in the hepatic veins. 



GLUCOSE IN THE URINE. 327 

ARTIFICIAL AND NATURAL DIABETES. 

It is observed that the amount of sugar increases in 
the blood of the superior hepatic veins when the 
pneunio- gastric nerves are irritated, when a special 
point in the wall of the fourth ventricle is pricked, 
when essence of turpentine, ether, or chloroform is in- 
jected into the vena porta, or simply when large 
proportions of these agents are inhaled, or, finally, 
when poisoning is produced by curarina, strychnia, 
or brucia. 

Let us follow step by step the research of Bouchardat, 
in order to study the theory of natural diabetes. And 
first we will recall the fact, that the digestion of 
amylaceous substances takes place in the intestines 
under the action of the pancreatic and intestinal juices, 
that the greater part of the starch is only changed 
into dextrine in the intestine, and that the further 
transformation of this dextrine takes place chiefly in 
the blood, under the action of the intestinal diastase 
absorbed simultaneously with the dextrine. 

Whenever there is an excess of glucose in the blood, 
this sugar passes into the urine. This fact may be 
demonstrated by injecting glucose into the veins : if 
there is but little, none is found in the urine ; if there 
is a large amount present, reagents will indicate its 
presence in the urinary secretion. 

The causes which produce an excess of glucose in the 
blood may be of two opposite characters : either the 
sugar is due to too great a secretion, or it may result 



328 ANIMAL CHEMISTRY. 

from an insufficient destruction ; but more often veri- 
table glycosuria characterized by a constant excess of 
sugar, is due to both of these causes combined. It has 
been demonstrated that the sugar passes into the urine 
whenever there is more than 3 to 5 grammes in the 
blood at one time. 

There may be an incompleteness in the destruction 
of the glucose in the blood, either because the oxygen 
is not present in sufficient quantity or because it meets 
with substances which are more easily oxidized. 

Diabetes will result when, the nutrition being very 
starchy, there is an excessive transformation of amyla- 
ceous substance into glucose in the digestive canal. In 
fact the glucose is observed to increase with the propor- 
tion of amylaceous food. In persons affected with 
glycosuria the transformation takes place in the stomach, 
and this fact consequently explains why all albuminoid' 
substances are susceptible of acting upon starch ; they 
differ only in the rapidity of their action. It has also 
been shown that if the pancreas of a pigeon be removed 
it will still be able to digest amylaceous substances. 
Bouchardat has also observed that the stomach of 
persons having glycosuria is generally very much en- 
larged, and that persons who have a tendency to 
diabetes prefer farinaceous food, that they eat a great 
deal, and also that they eat rapidly, which circum- 
stances occasion a longer sojourn of the food in the 
stomach. When an organ is much used it acquires 
greater strength, and it is not unreasonable to admit 
that under these circumstances the gastric juice may 



TRANSFORMATION OF FATTY SUBSTANCES. 329 

not be sensibly changed, and become incapable finally 
of dissolving amylaceous matter. 

Diabetes is accompanied by continual thirst ; hence 
it will be understood that since the food requires 
8 to iO times its weight of water for digestion, the 
gastric juice must be insufficient if the digestion of the 
farinaceous food takes place in the stomach at the same 
time as the albuminoid. 

The sugar in the urine of diabetic persons ordinarily 
disappears on submitting them to a diet formed ex- 
clusively of meat, if the disease is not too advanced. 

In general, any cause on the other hand which pro- 
duces a diminution of the respiratory phenomena tends 
to retard the destruction of glucose in the blood and 
produce diabetes if the tissues are saturated with 
glycogenic matters. 

TRANSFORMATION OF FATTY SUBSTANCES. 

It has been established by a large number of experi- 
menters, who have operated upon different animals, that 
all of them not only assimilate fatty matters, but that 
they produce fat as well. Fat alone given as food pro- 
duces inanition. If animals be submitted to varied 
nutrition, there is much more assimilated fat found 
than there was in the food originally supplied them. 
Fatty bodies mixed with the other food facilitate 
growth. Amylaceous and saccharine substances are 
readily changed by digestion into fatty matters. It 
has not been demonstrated that nitrogenous foods are 
transformed into fats. 



330 ANIMAL CHEMISTRY. 

The Role of Mineral Compounds in Nutrition is but 
little understood. Iron exists in different parts of the 
body, and principally in the blood globules. 

Sodium chloride is found in most animal fluids. It is 
thought, as we have already stated, that this substance 
is the origin of the hydrochloric acid of the gastric juice, 
and of the soda, which is found in the intestinal juices. 
It is known that this salt forms a compound with glucose 
(p. 186), also the existence of a compound of sodium 
chloride and urea has been shown ; and this is the reason 
for the belief that salt assists in the transformation and 
elimination of sugar and of urea. It aids in the solution 
of albumen and casein in certain humours. It prevents 
the dissolution of the blood globules, of the chyle and 
lymph, and we have reason to believe that it, like other 
salts elsewhere, is an important factor in the absorption 
of liquids by different membranes. 

Weiske and Wildt (7-1874-123) have made inves- 
tigations as to the action of food poor in lime and 
phosphoric acid, upon animals of rapid growth. They 
experimented upon three lambs about two and a-half 
months old, and in a healthy condition, feeding one 
with food poor in lime compounds, one with food poor 
in phosphoric acid, and the third with the usual kind of 
food; while the latter prospered and gained 13.5 
pounds in fifty-five days, the first two lost thirteen and 
fourteen pounds in weight, and were by this time 
nearly dead. The animals having been killed, the com- 
position of their bones, as regards their inorganic con- 
stituents, were alike, but the amount of fat in the bones 



TRANSFORMATION OF FATTY SUBSTANCES. 331 

of the- animal fed with normal food was greater than in 
both the others. A diet poor in calcium and phospho- 
rous compounds does not affect the constitution of the 
bones as regards their mineral constituents. 

Sodium Phosphate is capable of facilitating the absorp- 
tion of carbon dioxide by the blood, and consequently 
it is regarded as playing an important part in re- 
spiration. 

Calcium Phosphate is found in the majority of animal 
substances. This salt forms the greater part of the 
mineral matter of the bones, it exists in the ash of 
albuminoid compounds. It enters the body dissolved 
in water by means of carbonic acid. 

This substance, as well as the calcium carbonate, 
magnesium phosphate, and silica assist in giving solidity 
to the animal structure, and Chossat has asserted that 
the bones of pigeons completely deprived of calcium 
phosphate become so thin as to break. Magnesium 
phosphate cannot replace calcium phosphate. 

Weiske (36-'77) has investigated the influence of 
common salt upon the live- weight and the disassociation 
of nitrogen in various animals, and ascertained : that if 
the amount of salt in the food increases, and the animal 
be allowed all the water it desires, the amount of water 
consumed increases ; that with the increase of salt in 
the food and the consumption of water, as far as an 
increase in the production of urine accompanies the 
same, the disassociation of nitrogen increases ; that 
when the salt is removed, the consumption of water, 
as well as the production of urine, and disassociation of 



332 ANIMAL CHEMISTRY. 

nitrogen, decreases; nevertheless the latter remains 
higher for a longer time than if a large ingestion of salt 
had not taken place. The increase in weight following 
a diet composed largely of salt is not due to increase in 
the amount of flesh, but to the accumulation of water 
in the body. Salt given in the food increases the desire 
for eatirig, but a notable increase or decrease in the 
digestibility of the food has not been proven. 



URINE. 333 



UBINE. 

Human urine in its normal state is a liquid of an 
amber colour, the concentration of which, and conse- 
quently the density, varies with the age, sex, and state 
of digestion. This secretion is much more abundant, 
relatively, in infants than in grown persons, but the 
urine of infants is also richer in water, paler and less 
dense than that of adults. Parrot and A. Robin have 
lately (9-82-104) studied the urine of newly -born 
infants, and find that the secretion amounts to four 
times as much, referred to the weight of the body, as 
in adults. 

The quantity of urine in woman is to that in man 
nearly in the proportion of 13 to 12. 

The urine of man is pale, and charged with water 
after abundant ingestions of this liquid. Normal 
urine is that obtained soon after rising, its density is 
about 1.018, it varies between 1.012 and 1.022; its 
density may fall as low as 1.003, and rise to 1.030 
after a hearty repast ; it is then yellow. 

Water is evacuated from five to six hours after 
having been taken into the system. The proportion of 
urine is extremely variable ; * ,200 to 1,300 grammes 

H 



334 ANIMAL CHEMISTRY. 

is about the mean in men in twenty-four hours ; 1,300 
to 1,400 grammes in women. But this quantity may 
sometimes increase to 2,000 grammes, and descend to 
900 grammes. 

The three principal causes which influence the 
amount of this secretion are : — 

1st. The nature of the blood ; a very aqueous blood 
increases it. 

2nd. The rapidity of circulation in the kidneys. 

3rd. The activity of the pulmonary and cutaneous 
respiration. The urinary secretion varies in inverse 
proportion to the respiratory phenomena; thus the 
quantity of urine emitted is greater in winter than in 
summer, in cold countries than in warm countries. 
After a cold bath the urinary secretion attains its 
maximum. 

Certain salts — nitre, for example — increases the 
quantity of urine ; they are denominated diuretics. 

Other substances retard and diminish this secretion, 
as cantharides, etc. 

The proportion of solids extracted from the body by 
the urine may vary from 40 to 80 grammes in twenty- 
four hours. 

Composition of Normal Urine of Man. 

Water. . . 936.76 931.42 932.41 
Solid constituents. 63.24 68.58 67.59 



1000 00 1000.(0 10(0.00 



INFLUENCE OF FOOD ON THE URINE. 



335 



The solids are composed of — 



Urea . 


. 31.45 


32.91 


32.90 


Uric acid 


. 1.02 


1.07 


1.07 


Lactic acid . 


. 1.49 


1.55 


1.51 


Aqueous extract 


. 1.62 


0.59 


0.63 


Alcoholic extract 


10.06 


9.81 


10.87 


Lactate of ammo- 








nium 


1.89 


1.96 


1.73 


Chloride of sodium 


L 






and of ammo- 








nium 


3.64 


3.60 


3.71 


Alkaline sulphate? 


> 7.31 


7.29 


7.32 


Sodium phosphate 


\ 3.76 


3.66 


3.98 


Calcium and mag- 








nesium phos- 








phates 


1.13 


1.18 


1.10 


Mucus. . « 


0.11 


0.10 


0.11 




63.48 


63.72 


64.90 
(Lehman.) 



INFLUENCE OF THE FOOD ON THE COMPOSITION OF 
THE URINE. 



Nature of the Food. 



Honey . . . . 
Animal . 4 . . 
Vegetable . . . 
Non-nitrogenous . 



Solids in 
1000 parts. 



Urea. 



Lactic 
Uric Acid. Acid and 
Lactates. 



67.82 
87.44 
59.24 
41.68 



32.498 
53.198 
22.481 
14.408 



1.183 
1.478 
1.021 
0.735 



2,725 
2.167 
2.669 
5.276 



Extractive 
Matters. 

10.489 

15.196 

6.499 

11.854 



(Lehman.) 



336 ANIMAL CHEMISTRY. 

Normal human urine is acid. This acidity is due 
to the action of the uric acid and other acids of the 
urine upon the alkaline phosphates. These acids 
deprive them of a portion of their alkali, and acid 
phosphates result. Uric or hippuric acid may also 
be found in excess in urine. 

The quantity of free acid evacuated in twenty-four 
hours represents 2. to 2.5 grammes of oxalic acid. 

The reaction of the urine depends upon the character 
of the food. In fact, this secretion is alkaline in herbi- 
vorous animals, since their food, which is very rich in 
carbon, forms bicarbonates with the bases which are in 
this secretion ; but the urine of an herbivorous animal 
may be rendered acid on submitting it to a diet of flesh 
food. The urine of herbivorous animals is turbid, and 
contains urea, hippuric acid, and a small quantity of 
phosphates ; it does not contain uric acid. 

Inversely the urine of carnivorous animals is acid 
and clear. It is rendered alkaline by forcing the 
animals to an exclusive vegetable diet. 

The urine of carnivora contains more urea and uric 
acid than that of man or herbivorous animals, while 
hippuric acid is wanting in it. Regarding the occur- 
rence of phenol, E. Bauman has recently observed that 
albumen and pancreas in putrefying form a certain 
quantity of phenol, and he believes in this reaction can 
be found an explanation of the existence of phenylsul- 
phates in the urine of dogs fed exclusively with meat 
(60-77-685). 

Violent exercise, fatigue, and excesses render human 



AMMONIACAL URINE. 



337 



urine alkaline. This fact is due to the combustion 
which, under these circumstances, transforms the uric 
acid into urea, and this body does not possess, like uric 
acid, the property of removing from the phosphates a 
portion of the alkali which they contain. 

Gosselin and A. Robin (9-78-72) have made experi- 
ments upon animals, injecting ammoniacal urine sub- 
cutaneously, and found that animals subjected to this 
treatment became feverish, and when larger quantities 
were injected they died. Thus in diseases of the 
bladder, the ammoniacal urine, if reabsorbed, must be 
deleterious, hence it would be advantageous to the 
patient that the amount of ammonium carbonate in the 
urine be reduced ; this, according to investigations of 
Gosselin and Robin, is effected by the administration 
of benzoic acid. Pasteur (9-78-46) claims that the 
ammoniacal nature of urine is due to the action of a 
ferment which obtains entrance through the urinary 
passages, or sometimes is introduced mechanically by 
means of chirurgical instruments. He recommends, 
therefore, that the instruments before being used be 
plunged into boiling water, or heated, then quickly 
cooled, and at once employed. 

A, Lailler (9-78-361) is of the opinion that the 
ammoniacal fermentation of urine depends in a great 
measure on the amount of mucus it contains. 

Gubler (9-78-1054) asserts that the decomposition of 
urea into ammonium carbonate, as is the case in the 
bladder in certain diseases of this organ, is due to small 
pus-corpuscles (neocytes). 



338 ANIMAL CHEMISTRY. 

W. Zuelzer (60-1875-1670) has lately found that 
after a diet composed wholly of meat, the urine of a dog 
contained for every 100 parts by weight of nitrogen, 12 
to 14 of phosphoric acid ; when fed with potatoes and 
bread, it contained 20 to 30 of phosphoric acid to 100 
of nitrogen. In a healthy man, 20 to 25 years of age, 
the food being mixed and sufficient, the urine contains 
17 to 19 of phosphoric acid to 100 of nitrogen ; with a 
diet of meat the proportion of phosphoric acid decreases, 
with a vegetable diet it increases. The time of day 
and the state of health have great influence upon the 
relative proportion of these two substances. Under 
normal conditions a man eliminates 12 to 14 of sul- 
phuric acid, 0.3 to 0.7 of lime, and 0.6 to 1.0 of 
magnesia to 100 of nitrogen . 

The urine, on leaving the body, deposits mucus after 
a certain time ; it often also deposits urates, especially 
during fevers. But its acidity soon increases, in 
consequence of the formation of more uric acid ; this 
acid is often seen to deposit in the form of rhomboidal 
prisms. Other acids are also formed, chiefly acetic and 
lactic acids. At the end of a few days the urine loses 
its acidity and becomes decidedly alkaline from the 
formation of a considerable quantity of ammonium 
carbonate. This salt is formed from the urea thus : — 

CO" \ CO" ) n2 

H 2 N+2H 2 0=2(NH 4 ) j U 
H 2 ) 

This transformation of urea is favoured by the 



NORMAL CONSTITUENTS OF THE URiNE. &39 

presence of the mucous sediment which urine deposits 
when exposed to the air, also by the action of beer, 
yeast, and albuminoid substances. 

It is a true fermentation, accompanied by the 
development of an organized vegetable substanee 
(Torulacece), which reproduces itself by germination. 
Often its action is impeded by the formation of infusoria, 
which maintain the acidity of the urine for a long 
period. Cohn finds the organisms to be Micrococus ureae. 

NORMAL CONSTITUENTS OF THE URINE. 

Of the solid constituents, urea is the most abundant. 
The urinary secretion in man furnishes about 30 
grammes of urea in 24 hours, but this quantity may 
vary greatly. The average in women is 20 grammes ; 
it falls to 9 grammes in old men. A very nitrogenous 
diet increases it, while food which is poor in nitrogen 
diminishes it. Urea does not even disappear in an 
animal rigorously kept without food ; it is then formed 
at the expense of the tissues. 

When the urinary secretion increases, even though 
from the drinking of large quantities of water, the 
amount of urea produced also increases. It augments 
likewise, according to some authorities, during severe 
physical labour. 

We may admit, in general, that urea diminishes 
when the circulation of blood is sluggish, and that it 
increases when the circulation becomes active. 

There is only a very small quantity of urea in the 



340 # ANIMAL CHEMISTRY. 

blood; it becomes greater when the kidneys perform 
their functions badly. Urea is not formed in the 
kidneys. Dumas and Prevost showed in 1823 that the 
blood of animals, from which these organs have been 
removed, contains considerable amounts of urea. 

This fact has been confirmed by Bernard and 
Barreswil, who also showed that, after the removal of 
the kidneys, the gastric and intestinal secretions 
increase. The gastric juice remains acid but contains 
ammonia. When the animal becomes entirely ex- 
hausted, urea is found in the blood in a very notable 
quantity. 

Picart and Meissner have obtained the same results, 
which have, however, been doubted by Oppler, Perls, 
and Zalesky. The question has been taken up by 
Grehant, who conceived the idea of determining the 
amount of urea with the greatest care, and he has 
perfectly demonstrated that urea accumulates in the 
blood in consequence of nephrotomy. 

100 grammes of arterial blood contained : 

Urea. 
Before nephrotomy . . .0.088 grammes. 
Three hours and forty minutes later 0.093 „ 
Twenty-one hours later . . 0.252 „ 

Twenty-seven hours later . . 0.276 „ 

The urea increases, therefore, after the operation, 
and the increase takes place in a continuous manner 
proportional to the time. 



URIC ACQ). 341 

The ligature of the ureters renders the kidneys 
totally inactive, for the blood which leaves this organ 
is found to contain the same quantity of urea as on 
entering. Hence, after the ligature of the ureters, 
following nephrotomy, urea accumulates in the blood. 

The amount of urea excreted by man represents very 
nearly the whole amount of nitrogenous food which 
has failed to be assimilated, for the surplus is obviously 
found in the excrements, and they contain very little. 
The urine, therefore, is the liquid through which the 
nitrogen is eliminated, and the urea is almost the sole 
agent for effecting this. 

For this reason the determination of the urea is 
highly important as furnishing us with data relative to 
the elimination of the nitrogen from the body. 

Urea is not produced in the muscles ; though creatin 
is easily transformed into urea when out of the body, 
yet, in spite of the considerable quantity of creatin 
which exists in the muscles, no urea is found in 
muscular tissue. On the contrary, it is sufficient to 
take in the food, creatin, gelatin, or analogous matters, 
to observe that the urea is thereby formed in greater 
quantity in the urine. It is therefore rational to 
admit that these substances are oxidized in the blood, 
and that their nitrogen is eliminated in the form of urea. 

Uric Acid. — The urinary secretion furnishes each 
day 1.183 grammes of uric acid on an average (Wundt). 
It increases during digestion, and diminishes when the 
body is fatigued. In general it is produced whenever 
oxidation is impeded, and an increase in uric acid is 



342 ANIMAL CHEMISTRY. 

associated with a corresponding diminution of urea. 
This acid is found in the urine of persons affected with 
the gout. 

Uric acid, urate of ammonia, and urate of sodium 
are often deposited in urine a few hours after emission. 

Hipp uric Acid is found in small quantity in human 
urine. It increases with vegetable nourishment, in 
diabetes, and in certain other diseases. It is formed, 
molecule for molecule, when a benzoic compound is 
taken into the stomach. Lactic acid is only produced 
in the urine when digestion and respiration are im- 
paired. It is formed in fevers, and whenever digestion 
and circulation are impeded. 

Creatinin, and possibly creatin, exists in the urine. 

An adult throws off, in the urinary secretion, about 
1.16 gr. of creatinin in twenty-four hours. J. Munk 
(60-'76-1799) finds over *008 per cent, sulphocyan- 
hydric acid in normal urine. 

Stoedler considers phenic acid and two ill- defined 
acids — damolic and damaluric acids, — to which the 
odour of the urine is supposed to be due, as constant 
constituents of the urine. Scherer regards xanthin as 
existing normally in the urine, though only in traces. 
It is an amorphous substance, soluble in acids and 
boiling water. 

According to Schunck, urine contains always indican. 
This name is given to a body not as yet obtained in a 
crystalline condition, soluble in water, alcohol, and 
ether, and is essentially characterized by its property 
of decomposing in presence of strong hydrochloric acid, 



INDIGOGEN. 343 

furnishing, by combining with water, indigo and a 
saccharine matter, indiglucin. 

C ? ^^ w +2H 2 0=CANO+SO £ H ! A 

Indican Indigo Indiglucin 

The formation of this body accounts for the violet 
and reddish tints which are sometimes observed in 
urine undergoing decomposition. These phenomena 
take place only in the presence of atmospheric or other 
oxygen, as the indigo blue is very easily reduced. 

2C 8 H fi NO+H 2 =C 16 H 12 N0 2 

Urozanthin and still more appropriately indigogen 
are modern synonyms for indican. 

The substance which imparts to urine its yellow 
colour has been called urochrome by Thudicum. 
According to Heller, ether extracts from urine, which 
has been evaporated almost to dryness, a matter 
which he was not able to isolate, and which he calls 
uroxanthin. It is remarkable from the fact that, 
under the action of acids and in certain pathological 
states, it is transformed by oxidation into two other 
substances — one blue uroglaucin, the other red urrhodin. 

Since these substances have not been isolated with 
certainty, we shall not further dwell on them. 

Gtlucose.— Glucose is always present in normal 
urine, according to some chemists, though doubted by 
Seegen and Grorup-Besanez. 

The quantity of sugar present in normal urine 
amounts in twenty-four hours to 1 to 1.5 grammes 



344 AJS'IMAL CHEMISTRY. 

according to Briicke, also according to Bence Jones. 
It is therefore less than one-thousandth. 



FATTY BODIES, SALTS, AND GASES IN URINE. 

Fatty "bodies are found in the urine, but their 
proportion is very minute. 

The quantity of saline matter in the urine is con- 
siderable. It amounts to about 15 grammes in twenty- 
four hours. This quantity may increase to 25 grammes, 
and decrease to 8 grammes. It is less in women, and 
still less in children. Among these solid matters ere 
prominently phosphates, sodium phosphate, calcium 
phosphate, and magnesium phosphate. The quantity 
of phosphoric acid eliminated in the urine varies from 
3 grammes to 5 grammes in twenty-four hours. This 
acid increases during digestion. It diminishes in preg- 
nant women, and in the eighth month there is so little 
that both its reactions and those of calcium are hardly 
perceptible. Urine always contains alkaline chlorides, 
and chiefly sodium chloride. The quantity increases 
as the amount ingested increases, but the whole of this 
substance is not eliminated through the urine. The 
proportion of chloride increases after eating, and is at 
its' minimum during the night. Exercise increases the 
amount. The weight of chlorine evacuated in twenty- 
four hours is about 10 grammes. When all salt is 
removed from the food the amount diminishes in the 
mine, and remains fixed at 2 to 3 grammes per day, 



FATTY BODIES, SALTS, AND GASES IN URINE. 345 

which amount is derived from the tissues, and a rapid 
enfeeblement results. Sulphates are found in the 
urinary secretion. The quantity increases daring 
digestion ; it averages 2 grammes in twenty-four hoars. 

Normal acid urine contains no ammonium salts, bat 
contains them on becoming alkaline, some time after its 
voidance. The same is the case with the urine of 
herbivora, which is always alkaline. 

Many substances taken into the body which do not 
serve as aliments are found again in the urine, in case 
they are not capable of uniting with certain principles 
of the body to form insoluble compounds. Those 
metallic salts are among these latter, which form 
precipitates with albuminoid substances. 

Substances not precipitable in the organism and 
difficultly oxidized — such a& chlorides, iodides, sul- 
phates, nitrates, urea, quinine, and most fragrant and 
colouring matters — reappear unchanged in the urine. 
Oxidizable substances, on the contrary, undergo the 
same transformations which they sustain when acted 
upon by oxidizing agents. Alkaline sulphides are 
converted into sulphates, alkaline organic salts into 
carbonates, benzoic and cinnamic acids into hippuric 
acid, uric acid into urea, salicine into s;:ligenin and 
salicylic acid. The oxidation of certain other matters 
is more complete ; they furnish carbon dioxide and 
water, which are the ultimate products of the oxidation 
of organic bodies. This is probably also what occurs to 
many substances which never reappear in the urinary 
secretion, even after abundant ingestion of the same ; 



346 ANIMAL CHEMISTRY. 

such are niannite, ether, resins, the colouring matter 
of leaves, litmus, cochineal, amygdaline> anilin, 
camphor, etc. 

The rapidity with which these bodies pass into the 
urine depends upon their solubility. Potassium iodide 
is found in the urine in a few minutes after being 
administered. A longer time is necessary for the urine 
to assume the odour which is developed after eating 
asparagus and the inhaling of the vapours of turpentine. 

The gases of the urine are oxygen, nitrogen, and 
carbon dioxide. A mean of fifteen experiments made 
by Moring gave for a litre of fresh urine — 

Oxygen . . . - .0.65 c.c. 

Nitrogen 7.77 „ 

Carbon dioxide . . . . 15.96 „ 

These figures are probably too small, as the method 
by which the gases were determined was that of 
Magnus. 

Walking increases the amount of carbon dioxide. 

Carbon dioxide. Nitrogen. Oxygen. 
Urine during repose . 11.877 7.494 0.493 
„ when walking . 22.880 8.204 0.466 

The renal secretion of ophidians is solid, and com- 
posed chiefly of uric acid ; that of batrachians is liquid, 
and contains urea. 

The urine and excrements of birds contain chiefly 
acid urates, earthy phosphates, and a small amount of 
urea. 



ANALYSES OF DIABETIC URINE. 347 

Pathological States. — The urinary secretion in- 
creases in certain diseases (diabetes, polydipsia). In 
the first case its density may increase, as sugar is often 
present in large proportions ; it sometimes is as high as 
1.040. In polydipsia the density falls to 1.001. It 
diminishes in cholera, in diseases of the liver, and in 
fevers. 

Diabetes. — The quantity of sugar excreted in the 
urine may amount to 1200 to 1500 grammes in 24 
hours. 

Bouchardat, to whom we are indebted for important 
investigations relative to this disease, has shown that 
the formation of sugar may be lessened or even arrested 
by submitting the patient to a nourishment devoid of 
farinaceous and saccharine matter, by furnishing him 
for example, instead of ordinary bread, bread made 
of gluten or flour freed from starch by washing. 

The uric acid diminishes in quantity, or disappears 
in the urine of diabetic persons. 



ANALYSES OF DIABETIC URINE BY SIMON AND 
BOUCHARDAT. 

Simon. Bouchardat. 

l"^~"lL I. 

Density . . 1.018 1.016 

Water . . 957.00 960.00 837.58 

Solid constituents 43.00 40.00 162.42 

Urea . . traces. 7.99 8.27 



348 



ANIMAL CHEMISTRY. 

Simon. 



Uric acid . 
Sugar 

Alcoholic extract \ 
Aqueous extract > 
Salts . . ) 

Phosphates and 

mucus . 
Albumen . 
Oxide of iron 



I. 

traces. 
39.80 

2.10 



II. 

traces. 
25.00 

6.50 



Bouehardat. 

I. 

traces. 
134 42 

5.27 



0.52 0.80 0.24 

traces. traces, traces. 
traces. traces. 0.14 

Markownikoff (72-182-362) finds acetone and ethyl 
alcohol, and believes they are formed from the glucose 
by fermentation. 

Claude Bernard has shown that diabetes can be 
produced artificially by puncturing the " fourth 
ventricle." 

A slow poisoning of frogs with curari, the slow 
action of strychnia, the destruction of the spinal 
colurnu of frogs, etc., produce diabetes, Artificial 
diabetes is dependent upon the liver, as this state can 
never be obtained in a frog from which the liver has 
been removed. Sa'ikowsky has shown that if the for- 
mation of glycogenous matter in the liver of a rabbit 
be arrested, a result which is easily produced by the 
action of arsenates, this animal cannot become diabetic 
neither by curari nor by puncturing the fourth 
ventricle. 

F. W. Pavy (112-23-59; 24-51) obtains diabetes 



OTHER ABNORMAL STATES OF THE URINE. 349 

artificially in dogs by passing defibrir ated arterial 
blood through the liver ; saliva used instead of blood 
produced no glycosuria. Upon inhalation of oxygen 
Pavy noticed a like appearance of sugar in the urine. 

Albuminuria. — Albumen does not exist normally 
in the urine. When it is found, it is due either to the 
secretion of an albuminous urine by the kidneys, or 
to an admixture of blood, pus, or lymph. 

Albuminous urine is pale, acid, opaline, often of a 
density less than normal. As much as 20, 30 and even 
35 grammes have been found to have been secreted in 
twenty-four hours. 

The albumen increases after taking food ; it is at its 
minimum during the night. It increases with nitro- 
genous food. 

According to Lehman this albumen exists in two 
states, one part is the modification of albumen called 
metaglobuline and paraglobuline, and is precipitable by 
carbon dioxide. The other remains in the liquid after 
the passage of the gas, and is precipitated by ordinary 
acids. 

Anosmia. — The urine is pale and scarcely acid in 
anaemic persons ; it sometimes even becomes alkaline. 
It is rich in salts and poor in most organic con- 
stituents. 

Other Abnormal States of the Urine. — The 
urinary secretion decreases considerably in fevers, and 
is of a deeper colour and more dense than normal urine. 
Its acidity increases on account of the uric acid which 
forms abundantly, and of the lactic acid which is also 



350 ANIMAL CHEMISTRY. 

developed. The urea disappears in about the inverse 
proportion. The extractive matters increase ; the salts, 
and especially the sodium chloride, decrease. 

The proportion of urea increases in intermittent 
fevers, also at the commencement of typhoid fever. 

The quantity of urea, and especially that of uric 
acid, increases in inflammatory diseases. At the com- 
mencement of acute attacks the urea has been observed 
to amount to 60 grammes. The urine of persons affected 
with phthisis is richer in uric acid than normal urine, 
and fatty substances are also observed in it. 

The urea diminishes in nervous affections. 

In scarlatina and small-pox the urine contains am- 
monia, although it retains its acid reaction. 

A. Pohl found cholesterin (40-76-737) in the urine 
of an epileptic patient who had taken large doses of 
potassium bromide. 

Epithelial cells are found in large quantities m the 
urine in erysipelas, in scarlatina, in the commencement 
of Bright's disease, and in different urinary affec- 
tions. 

Fibrin and blood-globules appear in the urine during 
inflammation of the genital and urinary organs. In 
catarrh and in paralysis of the bladder the urinary 
secretion contains urate of ammonium. The urine is 
decomposed in the body of persons affected with catarrh 
of the bladder ; and in the urine are observed monads, 
vibrions, and mycoderms. 

Mucus is present in small quantity in normal urine. 
In various diseases of the genito-urinal organs, the 



OTHER ABNORMAL STATES OF THE URINE. 351 

mucus increases to such an extent as to render the 
urine turbid or milky. 

Pus is found in the urine when suppuration is esta- 
blished in the genito -urinal tract. 

The urine in jaundice contains the acids and colour- 
ing matters of the bile. These acids also pass into 
the urine in pneumonia. The bile itself is often found 
in the urine, and in this case boiling ether agitated 
with the urine takes on a green colour. 

The urinarj secretion diminishes or ceases entirely 
in cholera. 

The proportion of phosphates increases in nervous ' 
affections. The quantity of chlorine decreases chiefly in 
pneumonia, in obstinate diarrhoea, and during cholera. 

Chyle and casein are found in certain urines. 

The urine is brown in acute rheumatism ; it is red in 
many diseases in which the colouring matter of the 
blood passes into the urine ; it is almost colourless in 
megrim and in nervous affections. 

Von Merling and Musculus (60-1875-662) have 
examined the urine of a person who for a long time 
took 5 to 6 grammes of chloral hydrate every evening. 
The urine had an acid reaction, reduced alkaline copper 
solutions, contained neither chloroform, formic acid, nor 
sugar, but it contained chloral hydrate in small 
quantity, and turned the plane of polarization to the 
left ; this latter property was due to an acid which they 
called urochloral acid, obtained by evaporating the urine 
acidified with sulphuric acid, and extracting the acid 
with a mixture of alcohol and ether. This new acid 



352 ANIMAL CHEMISTRY. 

crystallizes in colourless silken needles, dissolves in 
water, alcohol, and a mixture of alcohol and ether, but 
is insoluble in pure ether ; with potassium, sodium, 
barium, and copper it gives well crystallized salts ; its 
composition is expressed by the formula 7 H 12 C] 2 6 . 

F. Baumstark (60-1874-1170) found in the urine of 
a person suffering with leprosy two peculiar colouring 
principles which he calls urorubrohrmatin and uro- 
Juchzohe matin. Urorubrohematin is a light bluish-black 
mass, insoluble in water, alcohol, ether, chloroform, or 
a solution of salt, soluble in alkalies, ammonium 
hydrate, alkaline phosphates and carbonates, alcohol 
containing acids, difficultly soluble in dilute sulphuric 
acid, and solutions of salt acidified with hydrochloric 
acid. The acid solution shows a characteristic absorp- 
tion spectrum. The formula obtained by analysis is 
C 68 H 94 N 8 Fe 2 26 (?). Urofuchsohematin is black, pitchy, 
insoluble in water, alcohol, ether, chloroform, acids, or 
acidified or non-acidified salt solutions ; it is soluble in 
alkalies, ammonium hydrate, alkaline phosphates and 
carbonates, and acidified alcohol. Analysis shows its 
formula to be C 68 H 10G N 8 O 26 (?). 

J. Miiller (60-1874-1526) found in the urine of a 
child pyromtechin. 

Urinary Sediments. — Human urine abandoned to 
itself often deposits solid crystalline bodies. During 
fever, urate of sodium is observed to form a short time 
after emission. These crystals are microscopic, and the 
appearance of the deposit is corpuscular and colourless. 



URINARY CALCULI. 353 

They are recognized by their disappearance when the 
urine is heated. 

The urine sometimes deposits, three or four hours 
after emission, prismatic crystals of uric acid having a 
rhombic base. 

When ammoniacal fermentation takes place in urine, 
a deposit of urate of ammonium is observed mingled 
with calcium phosphate or carbonate and ammonio- 
magnesium phosphate. This sediment forms whitish 
opaque grains, insoluble in water, soluble in acetic acid, 
and insoluble in ammonia. 

At other times, crystals of calcium oxalate cvncl 
ammonio-magnesium phosphate separate out. 

C. Stein (1-187-99) finds in certain rare cases in 
which the urine is alkaline that magnesium phosphate 
occurs in the sediment. 

There also separates out from the urine, under 
unusual and not well understood circumstances, an 
organic matter called cystin, containing sulphur. 

This substance is colourless, insoluble in hot water, 
and soluble in ammonia. 

Besides these crystalline substances, the urine de- 
posits organized matters ; mucus is alway present in 
it, sometimes pus, spermatozoids, blood globules, and 
coagulated albumen. 

Urinary Calculi. — This name is given to concre- 
tions of solid substances which form in the bladder. 
At times they escape with the urine in small grains or 
powder ; they are then known as gravel. 



354 



ANIMAL CHEMISTRY. 



These deposits are formed of various substances : 
uric acid, urate of sodium or ammonium, calcium car- 
bonate, oxalate or phosphate, ammonio-magnesium 
phosphate, cystin or xanthic oxide. 

The cystin may be obtained by treating the calculi 
with sodium carbonate and adding acetic acid to the 
liquid, when it deposits cystin in handsome hexagonal 
plates. 

This substance may also be obtained from the 
kidneys. 

A cystin calculus is soluble in caustic alkalies, and 
even in solutions of alkaline carbonates, with the ex- 
ception of ammonium carbonate. It is dissolved by 
the mineral acids, and precipitated by acetic acid. 
Heated in the air, it furnishes sulphurous oxide. 
Heated with an alkali it furnishes a sulphide. 

The nature of the calculi formed of cystin will be 
described further on. 

ANALYSIS OF URINARY CALCULUS. 



Urate of sodium 


. 




9.77 


Calcium phosphate . 


. 




34.74 


Ammonio-magnesium 


phosphate 




38.35 


Calcium carbonate 


. 




3.14 


Magnesium carbonate 


. . 




2.55 


Albumen . 


• • 




6.87 


Water and loss . 


° 




4.58 


• 


100.00 






(Lir 


Ldbergson.) 



ANALYSIS OF A CYSTIN CALCULUS. 



355 



ANALYSIS OF A FERRUGINOUS URINARY; CALCULUS. 



Ferric oxide 


. 38.81 


Alumina . 


. 23.00 


Silica 


. 17.25 


Calcium . 


. '. . 8.02 


Water 


. 10.89 


Loss. 


. 2.03 




100.00 




(Boussiiigault.) 



ANALYSIS OF A CYSTIN CALCULUS. 



Cystin ..... 
Calcium phosphate and oxalate . 



. 97.5 
. 2.5 

100.0 
(Lassaigne.) 



356 ANIMAL CHEMISTRY. 



ANALYSIS OF HEINE. 

The whole of the urine voided during 24 hours is col- 
lected and its volume measured ; of this 250 grammes are 
taken and allowed to stand for 24 hours ; or the urine first 
voided in the morning after sleep is taken for analysis. 

We commence by determining by means of litmus 
paper the reaction of this urine, and then determine its 
density ; as the presence of water or albumen diminishes 
its density, while the presence of sugar and salts 
augments it. There are used for this test special 
areometers or hydrometers, called urinometers. It is 
well to verify once for all the graduation of these 
instruments by means of urines whose specific gravity 
has been determined by the ponder al method. 



G-LUCOSE. 

We have already stated that abnormal urine may 
contain very large proportions of sugar ; such urine is 
usually sweet and denser than ordinary urine. It is 
susceptible of fermentation, turns the plane of polariza- 
tion to the right, and is but slightly coloured. 



QUANTITATIVE ANALYSIS OF URINE. 

If it is desired to extract the sugar, basic lead acetate 
is added in excess, the solution filtered, the excess of 
lead precipitated by hydrogen sulphide, again filtered, 
and evaporated until it crystallizes. 

The Qualitative Tests.— Its presence merely may 
be detected by the tests given on page 187. 

It should, however, be remarked that these reactions 
are not reliable unless a precipitate appears within one 
or two minutes boiling, as secondary reactions are 
produced with the other substances contained in the 
urine. 



quantitative determination of the sugar by the 
reduction of copper salts. 

Preparation of the Liquid. — "Weigh out 200 gr. 
of pure Eochelle salt, which place in a flask graduated 
to 1 litre ; add 500 c.c. of a solution of sodium hydrate 
of 24° Baume (D = 1.199), or 600 c.c. of a solution 
22° Baume (D =1.180). The solution is facilitated by 
agitating and slightly heating in a water bath. 

In another vessel dissolve 36.46 gr. of commercial 
copper sulphate, which has been purified by two or 
three recrystallizations, in 140 c.c. of distilled water, 
slightly heating. This solution is slowly poured into 
the first, stirring at the same time, that the precipitate 
may be dissolved. Binse out the vessel which con- 
tained the copper sulphate two or three times, and after 



358 



ANIMAL CHEMISTRY. 



placing the litre-flask in a vessel of cold, common 
water, add enough distilled water to bring the liquid in 
the flask up to 1 litre. This solution is very reliable, and 
may be preserved for months exposed to the light with- 
out alteration. For an improved reagent, see p. 187. 

Each 10 c.c corresponds to 0.050 gr. of pure cane 
sugar, or 0.0526 gr. of pure glucose. 

The determination is made by placing 20 c.c of the 
cupro-alkaline solution in a porcelain dish, bringing 
the same to boiling, and adding gradually — at the same 
time agitating with a glass rod — the saccharine urine 
from a burette graduated to tenths of a cubic centimetre. 
There is first formed a yellowish, then a red precipitate. 
"When the colour appears constant remove it from the 
flame ; the supernatant liquid soon becomes clear ; if 
it should appear greenish, again heat and add more of 
the urine drop by drop. The liquid must be neither 
greenish nor yellow. As long as there is any copper 
in the solution a drop of urine will produce an orange- 
coloured ring when it falls into the reagent. The 
amount of urine necessary to effect this will, of course, 
be an amount containing 2 x 0.0526 or 0.1052 gr. of 
glucose. 

Determination of Glucose in the Urine, by 
means of lead acetate. — In clinical experiments it is 
often sufficient to add to the urine a few drops of a con- 
centrated solution of lead acetate, separate the precipi- 
tate formed by filtering, and after bringing the filtrate 
to a known volume employ it in the same manner as the 
urine in the preceding operation. 



ANALYSIS OF URINE ALBUMEN. 359 

The lead salt has the effect of precipitating the 
foreign matter. The glucose is not precipitated by the 
acetate unless ammonium hydrate is added. 

When diabetic urine is highly charged with sugar it 
must be diluted with 5, 10, or 20 times its volume of 
water. 

Glucose can also be determined by adding yeast to 
the urine, and from the loss of carbonic acid in the 
resulting fermentation calculating the glucose present. 
It can also be estimated by means of a polarizing appa- 
ratus, such as is used for determining the strength of 
saccharine solutions for sugar refineries. 

As it is not within the scope of this work to supply 
elaborate instructions with regard to urine analysis, 
those desiring full details regarding the examination of 
urine for this or other constituents should consult some 
author on chemical analysis, or specifically on the 
chemical examination of the urine. A liberal amount 
of laboratory work is requisite, however, for such as 
would acquire a practical acquaintance with the 
chemistry of abnormal urine. 



ALBUMEN. 

Albumen is coagulated by heat and nitric acid. It 
is necessary to have recourse to these two reactions to 
detect with certainty the presence of albumen in urine. 
In fact, by simply heating the urine it often becomes 
turbid, owing to the precipitation of the earthy phos- 



360 ANIMAL CHEMISTRY. 

phates or carbonates; these salts may be recognized, 
however, by adding a drop or two of nitric acid, which 
will redissolve the precipitate formed. On the other 
hand, nitrj.c acid will produce a white precipitate m the 
nrine of a patient who has been taking various resinous 
remedies. 

When it has been found that four to five cubic cen- 
timetres of urine coagulates on heating, and that it 
continues to coagulate after adding eight to ten drops 
of nitric acid, we may conclude that this urine contains 
albumen. 

In order to estimate the amount of albumen we com- 
mence by ascertaining whether the urine is alkaline or 
not ; in case it is, it should be slightly acidulated with 
acetic acid. 100 c.c of the urine are taken and heated 
so as to cause coagulation — that is, until the urine just 
commences to boil. The liquid is then thrown upon a 
double filter, i.e., two filters of equal size and weight 
placed one within the other. The albumen remains 
upon the inner filter; it is washed with water, then 
with alcohol, and when it has well drained the two 
filters are dried at 110°. The difference between the 
weight of the filters with the precipitate and the filters 
empty is the weight of the albumen. 

Another determination to check the first may be 
made, precipitating the albumen with dilute nitric 
acid. 



DETERMINATION OF UREA BILE. 361 



UREA. 

"We have already mentioned the importance of noting 
the variations in the amount of urea, since these varia- 
tions give us light upon certain points in the process of 
nutrition. In order to ascertain whether a given urine 
is very rich in urea, a few drops are placed on a watch- 
glass with an equal volume of nitric acid and the glass 
floated on cold water ; after a few minutes crystals of 
nitrate of urea are to be seen. 

In order to determine the amount of urea, Leconte's 
method may be employed, which is based upon the 
oxidation of the urea by hypochlorites : — 
CH 4 N 2 + SNaCIO = 3NaCl + C0 2 + 2H 2 + N 2 . 

Carbon dioxide and nitrogen are disengaged: the 
former is absorbed by a solution of sodium hydrate, 
and the latter collected and measured ; from the volume 
obtained the amount of urea can be determined. 



BILE. 



I. Gives with sub-acetate of lead a greenish-yellow 
precipitate. 

II. Gives with a drop of nitric acid, green, blue, 
yellow, violet, and red coloration. 

III. Gives with a solution of white of egg, on 
adding nitric acid, a precipitate which is bluish-green ; 
whereas in the absence of bile it is white. 



362 ANIMAL CHEMISTRY. 

IY. Yields with tincture of iodine a green colora- 
tion. 

According to W. Gk Smith (7-[3] 8-299) this reac- 
tion distinguishes bile from the so-called indican. 



URIC ACID 

Is recognized qualitatively by the test given on page 
125. It is usually determined quantitatively by 
adding to a given amount of urine — not less than 
150 to 200 c.cm. — sufficient hydrochloric acid to fully 
precipitate the uric acid, and allowing the liquid to 
stand for twenty-four to thirty- six hours. Traces of 
uric acid still remain in solution which, however, 
according to Neubauer, are compensated for by the 
amount of the urine pigment which also falls with the 
uric acid. The precipitate is filtered off, washed, dried, 
and weighed. 

URATES. 

The urates of sodium and ammonium are among the 
constituents of normal urine ; they are often deposited 
after voidance when the urine has become cold ; a 
deposit is then observed which disappears on slightly 
heating. These urates may be recognized by charac- 
teristics which will be given under Urinary Deposits. 



INORGANIC SALTS IN URINE. 363 



HIPPURIC ACID. 

If hippuric acid is found to exist in notable quan- 
tities in urine, it may be determined by the method 
already given under the general discussion of this acid. 

CREATININ. 

Creatinin may be detected and even quantitatively 
determined by the following method: Milk of lime, 
then calcium chloride, is added to 300 to 500 c.c. of 
urine until a precipitate no longer occurs ; after being 
allowed to stand for a few hours the solution is filtered 
and the filtrate evaporated in a water-bath to the con- 
sistency of a syrup ; 40 c.c. of 90 per cent, alcohol is 
then added, and the whole allowed to digest for twenty- 
four hours. The clear liquid is decanted off, and a solu- 
tion of zinc chloride, as nearly neutral as possible, is 
added. A compound of zinc chloride and creatinin is 
formed, which is collected on a filter, washed with quite 
cold water, and dried. 

INORGANIC SALTS. 

The amount of salts in urine may be determined by 
evaporating 5 to 10 grammes in a porcelain dish. The 
residue is ignited at a slightly elevated temperature 
and weighed. 

The chlorides, sulphates, phosphates, lime, etc., may 
be determined by the methods usually employed in 
inorganic quantitative analysis. 



364 ANIMAL CHEMISTRY. 



TJEINAEY DEPOSITS. 

If the urine has produced a deposit, its nature may 
be determined by plunging one end of a glass tube, 
which has been drawn out to a point, down into the 
deposit, the other end being closed by the finger ; the 
finger is then removed, a quantity of the deposit 
allowed to run iuto the tube, the finger replaced, and 
tiie tube withdrawn. A certain quantity of the deposit 
is thus obtained, which may be tested with different 
reagents and examined under the microscope. 

Urine which contains an excess of uric acid is acid 
and limpid ; the deposit is then crystalline and slightly 
coloured, and is soluble in potassium or sodium hydrate, 
insoluble in ammonium hydrate or acetic acid. Nitric 
acid imparts a darker colour to urine rich in uric acid; 
a brown deposit may also be formed, which is soluble 
in alkalies. 

Urine containing urates becomes turbid shortly after 
voidance ; this deposit is white, or coloured and muddy. 
On heating it dissolves, as well as by adding potassium 
or sodium hydrate. Sometimes this deposit is coloured. 

Urine containing earthy phosphates may become 
turbid, but this deposit cannot be confounded with the 
preceding, as it does not dissolve on heating, is soluble 
in acetic acid, while not soluble in potassium or sodium 
hydrate. 

Urinary deposits formed of calcium oxalate are white; 



URINARY DEPOSITS. 365 

they are insoluble in ammonium hydrate and acetic 
acid ; they also do not dissolve on heating, but are 
soluble in mineral acids. If the deposit were formed 
of calcium carbonate, it would dissolve in acetic acid 
with the disengagement of carbon dioxide. Deposits 
of ammonio-magnesium phosphate are white ; soluble in 
acetic acid, insoluble in ammonium hydrate. 

Urine containing cystin has an acrid and even 
repulsive odour. It furnishes a deposit which does 
not dissolve on heating, and is soluble in ammonium 
hydrate. 

Certain urines become turbid on account of the 
mucus they contain, or because decomposition has set 
in. The presence of blood renders the urine red, the 
presence of bile greenish. Urines are sometimes met 
with which are whitish or opalescent; agitation with 
ether renders them clear. Blue and blackish urines 
also occur. 

If a drop or two of a urinary deposit is viewed 
through a microscope magnifying 250 diameters, and 
the preceding reactions employed, they will appear 
much more distinct. We would, however, add the 
following : 

Uric acid occurs in crystalline plates of a diamond 
shape ; their angles are often rounded off. These 
plates are often isolated, sometimes united in the form 
of rosettes and stars, and rarely in the form of needles. 
The urates are sometimes amorphous, sometimes 
crystalline. Deposits of urates may be distinguished 
from those of uric acid by their solubility in hot 



366 ANIMAL CHEMISTRY. 

water. They are generally found when the urine is 
alkaline. 

Crystals of urates, heated with a small quantity of 
nitric acid, give a residue of uric acid. More nitric 
acid forms alloxan, as do deposits of uric acid, and 
this yields a characteristic red colour with ammonium 
hydrate. 

Calcium phosphate is amorphous. 

Ammonio-magnesium phosphate occurs in prismatic 
crystals. 

Calcium oxalate crystallizes in regular octahedrons. 

Cystin, C 3 H 7 NS0 2 , occurs in beautiful hexagonal 
plates. It is obtained by treating the deposit with 
ammonium hydrate, and allowing the liquid to stand ; 
the cystin separates out, and by the aid of the micro- 
scope the form of the crystals may be distinctly seen. 
Under these conditions the uric acid would not dis- 
solve, a fact which permits of distinguishing between 
deposits of cystin and those of uric acid. Cystin is 
neutral, insoluble in water, alcohol, ether, or acetic 
acid. It is soluble in the mineral acids, also in oxalic 
acid. Ignited on platinum foil, it gives off an allia- 
ceous odour. It is coloured, like uric acid, upon 
treatment with nitric acid and ammonium hydrate. 
It dissolves in alkaline solutions. Heated with potas- 
sium or sodium hydrate in presence of lead oxide, it 
blackens on account of the formation of lead sulphide. 
Cystin is of rare occurrence, and its physiological 
and chemical relations have not been fully studied. 
Loebisch (1-182-231) has shown that no diminution 



URINARY CALCULI. 



367 



of urea or uric acid occurs in cases of cistinuria, 
though earlier investigators, and recently also Nieman 
(1-187-101), have come to the conclusion that uric 
acid at least decreases. Nieman established in the 
same research that there is no change in amount of 
sulphur in urine by reason of the presence of cystin. 

Pus may be recognized by the spherical globules, in 
which two or three nuclei are observed, on the addition 
of acetic acid. This matter is converted into a jelly- 
nke mass in contact with potassium or sodium hydrate. 

Mucus may be distinguished by its ropy consistency 
and its coagulation with acetic acid ; various kinds of 
cells are observed floating in the liquid. In these 
deposits epithelium cells are almost always found ; they 
are oval or irregular. 

We also find in urinary deposits : 

Blood Globules. — If the urine remains acid, they 
appear as quite characteristic discs ; if the urine 
becomes alkaline, they are destroyed. 

Tube Casts, — These may be: epithelial, fibrinous, mu- 
cous hyalin, (or colloid) and amyloid. 

The first have special diagnostic importance in diseases 
of the kidneys. These casts are generally nearly straight, 
though sometimes curvilinear, and not unfrequently are 
difficult to find. The epithelial cells which cover them 
are nearly normal in appearance. 

Epithelial Cells. — These may originate from the kidney, 
the bladder, the ureters, or the canal of the urethra. 

Vibrions. — Linear in form, and exhibiting character- 
istic movements. 



368 ANIMAL CHEMISTRY. 



UEINAEY CALCULI. 



Physical Aspect. — 1. Uric Acid. — Form, round ; 
colour, brown or reddish ; fracture, earthy or partially 
crystalline. When sawn through, a powder is obtained 
resembling the sawdust of wood. 

2. Urate of Ammonium. — These calculi are small, 
and of a clay or ash colour, with an earthy fracture. 
They are formed in concentric layers. 

3. Cystin. — These calculi are voluminous, pale 
yellow, rounded in form, glossy, crystalline, and 
sometimes striated. 

4. Cafcium Oxalate. — Calculi of this substance are 
called mulberry calculi, from their resemblance to the 
fruit of the mulberry-tree, their surface being covered 
with rounded tubercles. They are usually grey, though 
sometimes dark brown, which colour is due to the 
organic matter which covers them. Their fracture 
usually is granular, sometimes crystalline. 

5. Ammonio-magnesium Phosphate. — These calculi are 
white, crystalline, semi-transparent, covered with small 
brilliant crystals ; they are very easily pulverized. 

6. Calcium Phosphate. — These calculi are white, 
amorphous, and formed in concentric layers. 

The following table indicates in brief the method to 
be followed in examining different calculi. "We should 
mention , however, that calculi are not always composed 
of a single substance ; they are quite frequently formed 
of several compounds. This table of reactions applies 
as well to urinary deposits. 



CHEMICAL EXAMINATION. 



369 




370 ANIMAL CHEMISTRY. 

CUTANEOUS SECRETIONS OR TRANSPIRATIONS. 

We include under this head the products of the 
sebaceous follicles, of the glands of Meibomus, and the 
wax of the ears. 

These contain an albuminoid substance, of which 
but little is known, neutral fatty bodies (stearin, olein), 
epidermic cells, and epithelium and other cells, sodium 
chloride, ammonium chloride, and alkaline and earthy 
phosphates. 

SWEAT. 

The quantity of this secretion has not yet been 
determined. It is, however, known that it is quite 
large, and it is believed to be more than half of that 
of the pulmonary exhalations. 

It is obtained by pressing sponges against the skin 
while in perspiration, and afterwards washing these 
sponges with water. 

Sweat is an acid liquid, of an odour variable with 
individuals, and of a saline taste. It leaves 1 to 2.5 
per cent, of fixed substances on evaporation at 100°. 
Sodium chloride, mixed with potassium chloride, forms 
two-thirds of this residue. Alkaline phosphates have 
not been found in it. Its acidity is due to acids of the 
fatty series ; the most abundant is formic acid associated 
with small quantities of acetic and lactic acids. Favre 
has detected in it the existence of a special acid — 
sudoric acid. 

Sweat contains fatty matters derived from the 



SPERMATIC FLUID, OR SEMEN. 371 

sudorific and sebaceous glands arid a nitrogenous sub- 
stance (possibly urea), which, readily changes into am- 
nioniacal salts. In uraemia, the perspiration of the 
face contains a considerable quantity of this substance. 
The sweat appears milky, on account of the epithelial 
cells with which it is charged. It contains nitrogen 
and carbon dioxide gases. 



THE SPERMATIC FLUID, OR SEMEN, 

Is viscid, opaque, heavier than water, and possesses 
a marked odour. Heat does not coagulate it. It 
is precipitated by alcohol and acids. 

It is formed of a colourless fluid, in which float a 
large number of very minute bodies, called spermato- 
zoids. In man they have a flattened or oval body, to 
which is joined a long filiform " tail." 

The movements are principally executed by the tail, 
which has a sort of vibratile undulatory motion. 

The seminal liquid gelatinizes after emission. This 
effect is attributed to an albuminoid matter called 
spermatin, which is a substance resembling globulin and 
mucin. Heat does not coagulate its solutions. Acetic 
acid renders them turbid, and an excess of the acid 
re-dissolves the precipitate. These solutions are pre- 
cipitated by potassium ferrocyanide and nitric acid. 

After having been evaporated to dryness, this sub- 
stance no longer dissolves in water, but is dissolved in 
very dilute alkaline solutions. 



372 ANIMAL CHEMISTRY. 

The fecundating property of the spermatic fluid rests 
in the spermatozoids. They preserve vitality for a long 
time in the urine, and even in a dry state. If a cloth 
impregnated with dry sperm be moistened and placed 
on the stage of a microscope, the active spermatozoids 
are readily perceived. Spots of semen heated slightly 
for a few minutes assume a dark yellow colour. 

The seminal liquid contains in suspension, besides 
the spermatozoids, white granular corpuscles, mucus, 
and debris of epithelium. It holds in solution, in 
addition to spermatin, lecithin, 'various fatty bodies, 
sodium carbonate — which renders it alkaline — sodium 
chloride, and phosphates. 



MTJCUS FLUIDS OF THE SEEOUS 
MEMBRANES. 

Mucus is a viscous, ropy liquid, containing epithelial 
cells and small colourless corpuscles, few in number in 
a normal state, but which increase greatly when the 
membranes are inflamed. The composition of mucus 
in different parts of the body presents differences 
not yet determined. 

Mucin is the name given to that principle of which, 
however, little is known, imparting to mucus its ropy 
consistency. It is found in a number of the fluids of 
the body. Eichwald has given a process by means of 
which he extracts this substance from different liquids 
or tissues. 



mucus. 373 

It is most readily extracted from pulmonary expec- 
torations. 

These are diluted with water, and an excess of acetic 
acid added. The turbid liquid is washed on a filter with 
dilute acetic acid as long as the filtrate gives a precipitate 
with potassium ferrocyanide. The solutions are then 
treated with lime water and the mucin precipitated 
from the solution by acetic acid. This body appears to 
be largely soluble in water ; it is precipitable by 
alcohol and dilute acids, and soluble in alkalies. 

It is distinguished from albumen in not coagulating 
by heat. It also furnishes tyrosin under the action of 
dilute sulphuric acid. 

Gk Gaelchli (18-78-77) found that mucin on putre- 
fying generated indol, phenol, and a sugar-like 
substance. 

Normal mucus does not contain albumen. 

An analysis of nasal mucus by Nasse yielded : 

Water 933.7 

Mucin 53.3 

Lactates and extract soluble in alcohol 3.0 

Extract soluble in water and phosphates 3.5 

Alkaline chlorides . . . ' . 5.6 

Sodium hydrate ..... 0.9 



1000.0 



374 ANIMAL CHEMISTRY. 

Urine left standing for a short time often deposits 
mucus which is whitish, soluble in the alkalies, and 
partially in acids. It facilitates the transformation of 
the urea present into ammonium carbonate. 

Serosity effects the lubrication of various surfaces of 
the body, preventing friction ; its composition varies 
slightly in different organs. Albumen, mucus, and 
soda are ordinarily found in it. 

Synovia is the serosity which lubricates the joints. 
It is dense and slightly alkaline. It differs from mucus 
in containing albumen. 

According to Berzelius, it contains : — 

Water 926 

Albumen 64 

Extractive matters and soluble salts 6 

Calcium phosphate . . . 1.5 

Its composition, however, varies according to amount 
of exercise taken. 

ANALYSIS OF THE HYDROCEPHALUS FLUID. 



Mucus with a trace of albumen 


0.112 


Sodium carbonate . 


0.124 


Sodium chloride 


0.664 


Potassium chloride and sulphate 


traces 


Calcium phosphate 


» ?> 


Magnesium phosphate . 


► ;» 


Iron phosphate 


0.020 


"Water 


99.080 




100.000 




(Marcet.) 



COLLOIDIN. 


6 


ANALYSIS OF THE HYDKOPSICAL FLUID. 


Albumen .... 


2.38 


Urea 


0.42 


Sodium chloride . 


0.81 


Sodium carbonate . 


0.21 


Sodium phosphate, with traces 


of 


sodium sulphate 


0.06 


Mucous substance . 


0,89 


Water 


95.23 




100.00 




(Marchand.) 



375 



VESICULAR SEROSITY. 



Coagulable albumen . . . 5.25 

Albumen more soluble in water . 0.50 

Salts 0.26 

Water 93.99 



100.00 
(Brandes and Reimanri.) 

Colloid in. — (rautier, Oazeneuve, and Daremberg 
(97-[2] 21-482) have examined the jelly-like contents 
of a large ovarian cyst : they diluted the same with 
water, heated to 110 degrees in closed vessels, filtered 
after allowing to cool, dialyzed the filtrate in order to 
remove the salts, and precipitated with alcohol, whereby 
they obtained a white flocculent mass, soluble in water, 



376 



ANIMAL CHEMISTRY. 



and not precipitated either by metallic salts or mineral 
acids, but precipitable by tannic acid and alcohol. 
They have called this substance colloidin, and give as 
its formula C 9 H 15 N0 6 . According to Grorup-Besanez 
this body is closely allied to mucin. 



Human 


milk 


Cows' 


?> 


Goats' 


jj 


Asses' 


» 


Sheep's 


>> 



MILK 

Milk is a white, opaque liquid, inodorous while cold, 
and of a slightly sweetish taste. 
Its density, varies but little : — 



1.0320 
1.0300 
1.0341 
1.0355 

1.0409 



Human milk is alkaline. The milk of herbivora 
has generally the same reaction. That of carnivora is 
believed to be acid ; at least it acidifies so quickly when 
once drawn that it is difficult to state its reaction 
positively. 

Milk is formed of an almost colourless and trans- 
parent liquid, in which float an immense number oi 
oleaginous globules. These globules are visible 
only under the microscope; their size varies from 
0.0027 m.m. to 0.0041 m.m. They are opaque, and it 
is to these globules that the opacity of the milk is due. 
The fatty bodies of which they are formed are probably 



MILK. 377 

contained in an albuminoid membrane. If to milk we 
add a little potassium hydrate and ether, the alkali 
dissolves the membrane, the ether absorbs the 
fatty bodies, and the milk is changed into a limpid, 
transparent liquid. On placing some milk under a 
microscope, and moistening it with a drop of acetic 
acid, the membrane will be seen to be attacked, and the 
fatty bodies will immediately run together, while if it 
be simply agitated with ether, the globules remain 
unchanged. 

Robin, however, supposes that the milk globules 
have no special envelope, but are surrounded by a 
thin layer of a saponaceous matter formed of fatty 
bodies, salts, and albuminoid compounds. 

Milk left to itself separates into two layers ; that 
formed above, by the union of the globules, constitutes 
the cream, that below forms a white liquid, having a 
slightly blue tinge. 

On subjecting milk to a violent and prolonged 
beating, the globules unite and separate from the 
liquid, and butter is obtained. The fatty bodies of 
milk are formed of several principles: — 

Butyrin, caproin, caprin; about . . 2. 

Olein . 30. 

Margarin ...... 68. 

And a small amount of stearin. 

But these proportions are necessarily very variable. 
E. Tisserand (46- [3] 9-440) has summarized the 
following data :— 



378 ANIMAL CHEMISTRY. 

I. The separation of cream occurs the more promptly 
according as the temperature approaches 0°. 

II. The lower the temperature the larger the volume 
of cream and the yield of butter ; at the same time the 
butter milk, butter, and cheese, are all of a better 
quality. 

In human milk the mean percentage of butter is 
2.42. It ranges between 2.80 and 3.50 in cows' 
milk. 

According to different experimenters the margarin 
is very impure ; it contains stearin, myristin, and even 
other compounds. 

The lower layer contains various substances, of 
which the principal ones are : — 

Casein, an albuminoid matter previously described : 
the milk contains more of this substance after a 
nourishment of nitrogenous food than after one of 
vegetable matters. 

Sugar of milk 

Different salts, principally phosphates and chiefly 
calcium phosphate ; sulphates are not present. 

Milk allowed to stand in the air rapidly loses its 
alkaline reaction and becomes acid. It then coagulates. 
This effect is due to the lactic acid which forms spon- 
taneously in milk. It is formed by a fermentation 
called lactic fermentation. 

The sugar of milk is the substance which is trans- 
formed into lactic acid with the co-operation' of nitro- 
genous ferments. 

The coagulum is formed of casein and fatty sub- 



MILK. 379 

stances the liquid which remains is known as butter 
milk. 

A. Yogel (75-23-505) confirms the observations of 
Schwalbe (36-1872-833) that oil of mustard pre- 
vents the coagulation of milk ; according to his investi- 
gations the formation of lactic acid is in a great 
measure hindered by the presence of the oil of mustard. 
Oil of bitter almonds and oil of cinnamon prevent the 
formation of this acid to a less degree, while oil of 
turpentine, oil of cloves, benzol, carbolic acid, carbon- 
bisulphide, and hydrogen sulphide are almost without 
action. 

It is an alkali, soda, which holds the casein in 
solution in fresh milk, and milk may be kept fresh for 
a very long time by simply adding to it a few 
thousandths of an alkaline bicarbonate. On the other 
hand, milk will at once coagulate on the addition of 
an acid. 

Besides the acids, a large number of substances 
possess the property of causing milk to coagulate ; such 
are alcohol, tannin, different salts, many plants which 
are not acid, the flowers of the artichoke, of the thistle, 
and of the butter wort (Pinguicula vulgaris), which 
render it ropy, and especially rennet, a substance 
obtained from the stomachs of sucking calves. One 
part of rennet will coagulate 30,000 parts of milk, and 
the wooden vessels which have contained rennet, and 
which are used in dairies, may be used for a very long 
time for the operation without any subsequent addition 
of this substance. According to certain experimenters 



380 



ANIMAL CHEMISTRY. 



rennet effects the transformation of a certain amount of 
the sugar of milk into acetic acid ; according to others 
this transformation is produced by an albuminoid sub- 
stance called chymosin. The coagulum of milk is 
employed in making cheese. 

The nature of the food influences the character and 
quantity of this secretion. The butter increases if the 
food contains much fatty matter and when the food is 
vegetable. A mixed or animal diet diminishes the 
proportion of butter, and increases the proportion of 
casein and sugar. 

Fasting diminishes the secretion. The milk is then 
poor in sugar and salts, and becomes rich in fat and 
casein. 

During certain affections of the mammillary glands, 
mucus, infusoria, fibrin, and epithelial dSbris are found 
in the milk. 

Albumen occurs in t\e> milk when the mammillary 
glands are the seat of inflammation. In Bright's 
disease urea passes into the milk. 



COMPOSITION 


OF MILK, BY BOTTSSINGAULT. 






Human. 


Cow. 


Ass. 


Goat. 


Mare. 


T>og. 


Water 


88.4 
2.5 

4.8 

3.8 


87.4 
4.0 

5.0 

3.6 


90.5 
1.4 

6.4 

1.7 


82.0 
4.5 

4.5 

9.0 


89.63 
traces 

8.75 

1.60 


66.30 


Butter 


14.75 


Sugar of milk and sol- 
uble salts 


2.95 


Casein, albumen, and 
insoluble salts 


16.00 




99.5 


100.0 


100.0 


100.0 


99.98 


100.00 



COMPOSITION OF MILK OF A WOMAN. 



381 



Mott (100-6-364) finds milk of the negro race 
richer in solid matter than that of the Caucasian. 

According to recent investigations of Lieberman 
(1-181-102) there is another albuminoid substance 
in milk besides those given in the foregoing table, but 
which has not yet been isolated. 



COMPOSITION OF THE MILK OF A WOMAN, AT DIFFERENT 
PERIODS, BY SIMON. 



Days after 
Child- 
birth. 


Specific 
Gravity. 


Water. 


Dry 

Residue. 


Casein. 


Sugar. 


Butter. 


Mineral 

Salts. 


2 


1.0320 


82.80 


17.20 


4.00 


7.00 


5.00 


0.316 


10 


1.0316 


87.32 


12.68 


2.12 


6.24 


3 46 


1.180 


17 


1.0300 


88 38 


11.62 


1 96 


6.76 


3.14 


0.166 


18 


1.03O0 


89 90 


10.10 


2.57 


5.23 


1.80 


0.200 


24 


1.0300 


88.36 


11.64 


2.20 


5.20 


2.64 


0.178 


67 


1.0340 


89.32 


10 68 


4.30 


4.50 


1.40 


0.274 


74 


1.0320 


88.60 


11.40 


4.52 


3.92 


2.74 


0.287 


82 


1.0345 


9i.40 


8.60 


3.55 


3.95 


0.80 


0.240 


89 


1.0330 


88.06 


11.94 


3.70 


4.54 


3.40 


0.250 


96 


1.0334 


96.04 


10.96 


3.85 


4.75 


1.90 


0.270 


102 


10320 


90.20 


9.80 


3.90 


4.90 


80 


0.208 


109 


1.0330 


89 00 


11.10 


4.15 


4.30 


2.20 


0.276 


117 


1.0344 


89.10 


10.90 


4.20 


4.40 


2.00 


0.268 


132 


1.0340 


86.14 


13'. 86 


3.10 


5.20 


540 


0.235 


136 


1.0320 


87.36 


12.64 


4.00 


4.00 


3.70 


0.270 



According to Berzelius, skimmed cows' milk con- 
tains : — 

Casein, with a small quantity of butter 2.600 

Sugar of milk .... 3.500 

Alcoholic extract, lactic acid, lactates 0.600 

Potassium chloride . . . 0.170 



382 ANIMAL CHEMISTRY. 

Alkaline phosphate .... 0.025 
Calcium phosphate, lime combined 
with casein, magnesia, and traces 
of iron oxide .... 0.230 
Water 92.875 



100.000 

H. Eitthausen (18-77-348) has recently found in 
milk another carbohydrate, differing from milk sugar, 
and more resembling dextrin. 

FLESH. 

We can have only imperfect ideas in regard to the 
transformations which the plastic principles (albumen, 
fibrin, casein) undergo in being converted into assimi- 
lable matter and tissue, also as to the manner in which 
each organ selects from the nutritive substances the 
elements which are suited for its use. 

It is certain that albumen plays the principal rdle, 
for it is observed to give rise to fibrin and other nitro- 
genous substances under certain circumstances, and 
especially in the incubation of the egg ; certain physi- 
ologists have also thought that in digestion all nitro- 
genous substances are converted into albumen, and that 
in nutrition the albumen is changed into fibrin, a 
substance which, from the facility with which it coagu- 
lates, is the principal agent in the creation and renewal 
of the tissues, that is, of the solid portions of our 
bodies. 



MUSCULAR TISSUE. 



383 



These ideas are probably exaggerated, or at the least 
their correctness has not been demonstrated. 

Muscular Tissue. — The muscles are constituted of 
a reddish contractile tissue, formed of fusiform elon- 
gated cells and of striated filaments, constituting an 
external envelope, called the sarcolemma, and of inter- 
nal substances, from which a variety of fibrin, syntonin, 
may be extracted. 

This latter is probably the substance into which 
albuminoid matters are changed during digestion in 
the stomach (parapeptone). 

Solutions of syntonin in acids are not coagulated by 
boiling ; they are precipitated by chlorides and alkaline 
sulphates. Syntonin dissolves in caustic alkaline liquids 
and in dilute solutions of carbonates, and is reprecipi- 
tated when these solutions are neutralized, even in the 
presence of alkaline phosphates. This last character 
distinguishes it from the albuminates. 

The fibres of the muscles are surrounded hy a fluid 
which may be considered as the plasma of the muscles. 
It may be prepared according to Kiirme by removing 
the muscles of an animal recently killed, and freezing 
them at a temperature of about — 7°, whereby they 
become very brittle. They are pulverized in a well- 
cooled mortar, and thereupon subjected to a heavy 
pressure in an appropriate press. A liquid is thus 
obtained, which is placed upon a filter surrounded by 
a refrigerating mixture. The liquid, which filters 
very slowly, is opaline-yellowish, viscid, and alkaline. 
It coagulates at ordinary temperatures, furnishing 



384 ANIMAL CHEMISTRY. 

myosin, which may be readily obtained by causing the 
filtrate to fall into water at the ordinary temperature. 
If acid solutions of myosin are saturated, it is then no 
longer this body which precipitates but syntonin. Syn- 
tonin differs from myosin by not dissolving in solutions 
containing less than 10 to 12 per cent, of common salt. 
Myosin may also be. obtained more simply by pounding 
flesh with water containing 8 to 9 per cent, of common 
salt. After allowing this to stand twenty-four hours 
it is filtered by being pressed through cloth, and the 
myosin precipitates on pouring the liquid into water. 

The liquid which remains after the coagulation of 
myosin contains, according to Kiihne, two albuminoid 
substances, one coagulable at 75°, the other at 45°, and 
alkaiine albuminates ; also salts, which are chiefly 
phosphates, lactic acid, and lactates ; sugar and various 
organic substances, as creatin, creatinin, inosic acid, 
inosite, sarcosin, sarkin, and xanthin. This liquid is 
coagulable by heat, and of a red colour ; its acidity is 
due to lactic acid and acid phosphate of potassium, 
which may be extracted from the muscles by dilate 
alcohol. 

It is claimed by Fremy and others that there exists 
in the muscles a special acid, called oleophosphoric acid, 
and that this acid is combined with sodium. 

According to Dubois Eeymond, the muscles do not 
possess an acid reaction until after death, and while 
contractile their reaction is slightly alkaline. 

In certain pathological states, urea, uric acid, and 
various other products are present. 



COMPOSITION OF FLESH. 



385 



H. Struve (60-'76-623) finds in fatty muscular tissue 
a new body which gives the absorption spectra of blood, 
but is changed, unlike the latter, by the action of 
alkaline sulphides and acids. 



COMPOSITION 


OF 


FLESH. 








Pectoral Muscles. 






Man. 


Woman 


"Water 


. 


72.46 


74.45 


Muscular fibres, vessels, and 






nerves . 




16.83 


15.54 


Fats .... 




4.24 


2.30 


Extractive matters 




2.80 


3.71 


Cellular tissue . 




1.92 


2.07 


Soluble albumen 




1.75 


1.93 



100.00 100.00 
(Yon Bibra.) 

Flesh leaves from 2 to 8 per cent, of ash, formed 
chiefly of alkaline and earthy phosphates ; sodium 
chloride and sodium sulphate are also present, 

The brcth produced by digesting muscular tissue in 
water contains, according to Chevreul : — 

Water 988.57 

Organic substances dried in a vacuum 12.70 
Salts (phosphates, sulphates and chlo- 
rides of potassium, sodium, calcium, 
magnesium, and iron) . . . 3.23 

1004.50 



386 ANIMAL CHEMISTRY. 

Creatin, C 4 H 9 N 3 2 + H 2 0. 
Creatinin, C 4 H 7 N 3 0. 
Sarcosin, C 3 H 7 N0 2 . 

These three bodies have the highest importance in 
connection with the study of muscular tissue. 
Liebig found in : 

Muscular flesh of the ox . 0.69 creatin. 

„ horse . 0.72 „ 

Creatin is prepared by treating meat cut into very 
small pieces with cold water as long as anything is 
dissolved, and the solution evaporated ; the concentrated 
liquid, filtered, furnishes creatin. 

This body occurs in rectangular prisms, without 
taste or odour, soluble in 74 parts of cold water, but 
more soluble in boiling water. 

On being boiled with strong acids it furnishes creatinin. 

HOI + C 4 H 9 N 3 2 =H 2 + C 4 H r N 3 0,HCl 

Chlorhydrate of creatinin. 

This chlorhydrate decomposed furnishes creatinin as 
a crystalline alkaline substance, more soluble than 
creatin in both water and alcohol. Creatinin may 
be reconverted into creatin by boiling with lead oxide. 

It forms with zinc chloride a combination which is 
but slightly soluble in cold water. According to 
Neubauer, creatin does not exist in flesh, but creatinin 
only, and the creatin which is found is formed by the 
transformation of the creatinin. Creatinin also exists 
in urine, and in the muscles of the Crustacea. 



XANTHIN. 387 

On submitting creatinin to a prolonged ebullition 
with baryta water another substance is formed, called 
sarcosin. 

H 2 -f C 4 H 9 N 3 2 =CH 4 N 2 + C 3 H 7 N0 2 

Urea. Sarcosin. 

This body crystallizes in rhombic crystals, which are 
colourless, very soluble in water, somewhat soluble in 
alcohol and insoluble in ether. Sarcosin melts at a 
temperature above 100 D , and is volatile. It possesses 
the characters of glycocol and its homologous sub- 
stances. 

Inosic Acid. — The mother liquor of creatin is acid, 
and has an odour of meat broth. Extract of meat 
treated with baryta furnishes on evaporation inosate of 
barium, and the liquid contains inosite. The formula 
of inosic acid is usually given as C 5 H 8 N" 2 6 , though 
some authors regard it as C l0 H 14 N 4 O n (21-269). 

Xanthin. — C 5 H 4 N 4 2 . To prepare this substance 
muscular tissue is well beaten, and alcohol and water 
successively added as long as anything is dissolved. 
These two liquids are now united and heated, in order 
to coagulate the albumen and drive off the alcohol. 
The liquid is filtered, and lead subacetate added. The 
precipitate is collected, washed, and decomposed with 
hydrogen sulphide while suspended in water. The 
filtered liquid is boiled and evaporated. The xanthin 
deposits in a non-crystalline mass. It can also be 
prepared from the liver. Xanthin is soluble in cold 



388 ANIMAL CHEMISTRY. 

water, alcohol, and ether. It forms with acids salts 
which are generally crystallizable ; it is precipitated 
even from very dilute solutions by mercuric chloride or 
nitrate. 

It dissolves in alkaline liquids. If calcium hypo- 
chlorite be added to one of these solutions, a greenish 
precipitate is formed which becomes brown and then 
disappears. This reaction is quite delicate, and a 
useful test. 



OTHER TISSUES. 

Cells. — The cells are the simplest structures of .the 
body. Their mass is very minute, and their form 
variable. They are not always enclosed by an envelope, 
and they vary in their chemical nature. They contain 
one or more nuclei, and when new a gelatinous liquid 
(protoplasm), capable of contractile movements under 
the influence of chemical agents, of electrical or 
mechanical forces. If old, they contain different 
matters, derived either from modifications of the proto- 
plasm or the introduction of foreign substances. 

The protoplasm coagulates after death. It appears 
to contain myosin, also other albuminoid, fatty, and 
saline constituents. 

Areolar Tissue is chemically characterized by the 
action which hot water has upon it. 

At first it swells, assumes a jelly-like appearance, 
and finally dissolves, producing gelatin, which, on 
cooling, is of a tremulous consistency. 



tissues. 389 

Dilute inorganic acids and dilute alkalies also effect 
this transformation. There is believed to exist in this 
tissue a substance (collagene, glutine, geline) analogous 
with ossein, which, in contact with hot water, furnishes 
gelatin ; also a substance (elastin) not furnishing 
gelatin. « 

Tannin and mercury dichloride form with these 
matters imputrescible compounds. 

Cellular tissue is converted into a transparent and 
colourless jelly by the action of strong acetic acid ; but 
the fibre is not attacked, for if the acid be saturated 
with ammonia water it reappears in its ordinary 
condition. 

The elastic tissues do not dissolve even after an ebulli- 
tion of sixty hours, and do not furnish gelatin. 

Hydrochloric acid dissolves them, turning brown at 
the same time. With sulphuric acid they furnish 
leucin and not gelatin. This may be obtained quite 
pure by boiling cellular tissue with water, then with 
acetic acid, and macerating the residue with a dilute 
alkaline solution. To the product thus obtained the 
name of elastin has been given. 

The mucous areolar tissue differs chemically from 
ordinary conjunctive tissue, in that it does not furnish 
gelatin on being boiled with water. 

The reticular tissue of the cutis contains the pig- 
ment called melanin, the colouring matter of the skin. 
This tissue is not reproduced completely where destroyed, 
but is replaced by cellular tissue, and the cicatrix is 
due to the fact that this latter tissue is colourless. 



390 ANIMAL CHEMISTRY. 

The epidermis furnishes gelatin on boiling with water. 

It appears to contain iron, and H. P. Floyd 
(84-34-179) has found it to contain in the negro 
twice as much of this element as in whites. 

Sulphuric acid softens and dissolves it, nitric acid 
colours it yellow, alkalies dissolve it, the sulphides 
render it of a brown colour, and silver salts blacken it. 

The epidermis, hair, bristles, feathers, nails, horns, 
and epithelium have an almost identical composition. 





Epi- 
dermis. 


Epi- 
thelium. 


Hair and 
Bristles. 


Nails. 


Feathers. 


Horn. 


Carbon 


50.34 


51.53 


50.00 


51.00 


52.42 


50.94 


Hydrogen . 


6.81 


7.03 


6.40 


6.82 


7.21 


6.65 


Nitrogen 


17.22 


16.64 


17.00 


17.00 


17.89 


16.28 


Oxygen and 
sulphur . 


25.63 


24.80 


26.60 


25.18 


22.48 


26.13 



100.00 100.00 100.00 100.00 100.00 100.00 

The horny tissues are formed of cells containing 
nuclei which have united and dried. Indeed, when 
these different tissues are treated with alkaline solu- 
tions, ovoid cells are seen, each containing a nucleus. 
Sulphuric acid likewise renders this structure apparent. 
This tissue leaves about 1 to 1.5 per cent, of ash on 
ignition. 

Horn treated -with fused potassium hydrate and with 
dilute sulphuric acid, furnishes tyrosin and leucin. 

Hydrochloric acid renders it blue, nitric acid yellow ; 
aqua regia attacks it with energy. 

Feathers possess the same general properties. The 
colour of the feathers is due to different pigments, 
rarely soluble in water, sometimes in ammonia, and 



CARTILAGINOUS TISSUE. 391 

ordinarily in alcohol. They generally contain less 
oxygen and more silica than horn and analogous 
tissues. 

Hair has the same composition and chemical char- 
acters as horny tissue. 

Its colour is due to oils of various tints. With age 
this oily secretion ceases to be produced and the hair 
whitens ; the white colour seeming to be due to the fact 
that the tubes contain no secretion, but are filled with 
air. The fatty bodies of the hair are formed from the 
volatile acids of perspiration, and also of margarin, 
olein, and stearic acid. Hodgkinson and Sorby ob- 
tained (28-222-592) from black hair and feathers a 
black pigment, to which they ascribe the formula 

Hair contains 0.5 to 2.0 per cent, of inorganic sub- 
stances, containing a considerable proportion of iron 
and small quantities of silica. Mulder found in epi- 
dermis an organic sulphur compound he called keratin. 
Cartilaginous Tissue. — The cartilages are ordi- 
narily formed of a flexible tissue, whose composition is 
not greatly different as to its organic constituents from 
that of the preceding substances, though varying in 
organic composition with age and in the different parts 
of the body : — 

Carbon 50.91 

Oxygen 6.96 

Nitrogen 14.90 

Oxygen 27.23 

100.00 



392 ANIMAL CHEMISTRY. 

Hoppe-Seyler found in a proximate analysis of 
cartilage from the knee of a man aged twenty-two 
years : — 

H 2 75.59 

Organic matter . . . .24.87 
Inorganic matter . . . 1.54 



100.00 



This tissue is not homogeneous ; under the micro- 
scope it appears composed of a colourless fibre and cells 
containing granulated protoplasm. The matter of the 
cells is different from the gelatinous substance forming 
their envelopes. It does not dissolve in boiling water 
even under pressure. 

The cartilaginous substance proper, cartilagein, fur- 
nishes, with boiling water, a substance which resembles 
gelatin in its composition, but from which it differs in 
several characteristics, and especially by its giving a 
precipitate with acids, lead acetate, and alum, while 
gelatin gives no reaction with these substances. It is 
called by the name of chondrin. Chondrin turns the 
plane of polarization to the left. Treated with hydro- 
chloric acid it furnishes a variety of glucose (chondro- 
glucose) and various nitrogenous substances of which 
little is known. 

A distinction has lately been made between the 
cartilages just spoken of and the fibro-cartilages. These 
last contain a fibrous matter without nuclei, differing 



NERVE TISSUE. 393 

from the ordinary cartilaginous substance by producing 
with boiling water a substance which is but slightly 
precipitated by tannin. The fibro-cartilage of the knee 
must also be distinguished from the preceding, from 
the fact that it produces gelatin with boiling water. 

Cartilaginous tissue contains 55 to 15 per cent, of 
water, 2 to 5 per cent, of fatty bodies, and 1.5 to 6 
per cent, of mineral substances. 

Nerve Tissue. — Of it are composed the nerves, 
ganglia, brain, and the spinal cord. It is observed to 
contain cells and cylindrical tubes ; these are formed 
of an envelope of areolar and fibrous tissue and of a 
semi-liquid medullary substance (myelin of Yirchow), 
which refracts light strongly, and is sometimes observed 
to flow out when a nerve is cut. These tubes are 
united in bundles which are enveloped in a colour- 
less, lustrous, and fibrous membrane sometimes called 
neurilemma. 

This membrane may be rendered apparent by treat- 
ing nervous tissue with a cold dilute solution of caustic 
potassa, which dissolves the nervous substance with the 
exception of the neurilemma. This membrane is dis- 
solved, on the contrary, by hydrochloric acid and 
strong sulphuric acid ; it is not coloured yellow by 
nitric acids. 

The ganglions of the nervous centres are formed of 
cells of variable size, composed of a very thin envelope 
and a nucleus containing a dense liquid, in which are 
granules in suspension. 

Concentrated alkaline solutions attack and dissolve 



394 ANTMAL CHEMISTRY. 

the nerve cells and tubes. Strong inorganic acids 
shorten and thicken the fibres. An aqueous solution 
of iodine colours them bright yellow. A mixture of 
mercurous and mercuric nitrates renders them rigid 
and tenacious. 

The reaction of the nerves appears to be neutral 
during life, it becomes acid after death, and finally, at 
the moment when putrefaction sets in, it has an 
alkaline reaction. 

Different investigations made recently on the matter 
of the nerves and brain have shown that we are 
far from completely understanding its compositions ; 
Liebrich's protagon is now regarded as a mixture 
of W. Midler's cerebrin and lecithin, and the same 
may be said of Kohler's myeloidin and myeloidinic 
acid. 

The Constituents of the Brain, more or less 
constant and normal, thus far determined with apparent 
certainty are : — ■ Water, — albuminoid bodies resembling 
myosin, — elastin (?) — neurokeratin, — nuclein, — collagen, 
— soluble albumen, coagulating at 75°, — cerebrin and 
lecithin, — glycerinphosphoric acid, — fats (?), — cholesterin, 
inosit, — hypoxanthin, xanthin, kreatin, — lactates, — vola- 
tile fatty acids and uric acid. Inorganic substances : 
calcium, potassium and magnesium phosphates, iron 
oxide, silica, alkaline sulphates, sodium chloride, and 
fluorine. (Horsford.) 

Although very extended and repeated investigations 
of the chemical nature of the brain have been made, 



CONSTITUENTS OF THE BRAIN. 395 

it yet remains, chemically, one of the most incompletely- 
known animal organs. 

It was W. Mliller who first obtained the nitrogenous 
neutral body from the brain called cerebrin. It is 
extracted on coagulating by heat an aqueous extract of 
the cerebral substance ; this coagulum is separated and 
washed with water, and treated while boiling with a 
mixture of alcohol and ether, and filtered hot, White 
flakes separate out of the solution, which contains 
cholesterin, lecithin, and cerebrin. This matter is the 
cerebric acid of Fremy. Cerebrin has the formula 

It is dissolved by sulphuric acid, the solution being 
of a purple colour. It is rendered resinous by hydro- 
chloric acid, and is transformed by boiling nitric acid 
into an oil which solidifies on cooling. Grobley claims 
to have also found cerebrin in the yolk of eggs. 

E. Bourgoin (60-[2] 21-482) purifies cerebrin from 
the phosphorous compound which ordinarily adheres to 
it by treating the same with a sufficient quantity of 
strong alcohol, and gradually warming ; the cerebrin 
dissolves before the alcohol begins to boil, and the 
phosphorous compound deposits itself on. the bottom of 
the vessel ; the cerebrin separates out of the decanted 
solution on cooling. The cerebrin should be again 
subjected to a similar treatment. Bourgoin regards the 
protagon of Liebreich (36-1865-647) as a mixture of 
cerebrin with this phosphorous compound. 

Pure cerebrin shows the following composition : — 



896 ANIMAL CHEMISTRY. 

Carbon 66.35 

Hydrogen 10.96 

Nitrogen . . . . . 2.29 
Oxygen 20.40 

Lecithin, though a constituent of the brain, is best 
obtained' from the yolk of eggs. It is an imperfectly 
crystallizable body, easily fusible, with a waxy lustre, 
soluble in ether and alcohol, and in general very easily 
decomposed. There appear to be various lecithines 
with different radicles ; one of the most common 
appears to have the radicle of stearic acid, its empirical 
formula being C 44 H 90 NPO 8 . (Thudicum.) 

The mineral salts constitute about 5 per cent, by 
weight of the brain in a dry state. When the brain is 
in full action the elimination of phosphorus appears to 
be greater than when it is in repose, since the quantity 
of alkaline phosphates in the urine increases. 

The composition of the spinal cord, of the medulla 
oblongata, of the nervous fibres and ganglions is very 
similar to that of the cerebral substance. The medulla 
oblongata contains the largest proportion of fatty 
bodies. 

Osseous Tissue. — The bones are formed of solid 
mineral matter (about 70 per cent.), and of an organic 
cartilaginous tissue, in which is found a principle called 
ossein, furnishing gelatin with boiling water. The 
bony structure is pierced with numerous cavities. 
Many are visible to the naked eye ; others are extremely 
minute canals, which penetrate in all directions, forming 
a complete network, which admits of communication 



CONSTITUENTS OF BONE. 397 

between the most remote points of the structure ; these 
canals are concerned in the nutrition of the tissue. 

The medullary cavity and the cells of spongy hones 
have a membranous cellular tissue and blood-vessels. 

The canaliculi contain only nerves and blood- 
vessels. 

Marrow is formed, according to Berzelius, of — 

Fat .96 

Blood-vessels, membrane ... 1 
Extractive substances .... 3 



100 



According to Eylerch, the fatty matter of marrow is 
constituted of three ethers of glycerin, whose acids are 
the palmitic, medullic, and elaidic. 

The first is the most abundant. 

Bones deprived of their fat and periosteum, are, 
according to Berzelius, composed of — 

Man. 

/ Calcium phosphate (tribasic) 53.04 
Mineral portion Calcium carbonate . 11.30 

J Magnesium phosphate . 1.16 

\ Sodium chloride and carbonate 1.20 
Organic portion ( Cartilage (ossein) . 32.17 

(Blood-vessels . . 1.13 



100.00 



Ossein has, as a special characteristic, the property of 
being transformed by the action of boiling water into 

M 



398 ANIMAL CHEMISTRY. 

gelatin. The membrane which covers the walls of the 
osseous canals is formed of an albuminoid substance 
insoluble in boiling water. Nitrogenous bodies derived 
from the blood-vessels and nerves are also found in the 
bones, as well as fatty matters. 

On treating bones with a dilute alkaline solution 
the ossein is dissolved, and the mineral portion remains, 
retaining its original shape. 

The composition of bone does not vary greatly with 
age, except that the hard and compact portion of the 
bones diminishes in aged people, and is replaced by a 
spongy and more brittle material ; also in children it 
contains more water, and is more elastic. It has been 
observed that in lower animals the proportion of calcium 
carbonate increases with age. 

The composition of the bones of different species of 
animals differs but little ; yet the bones of birds and 
herbivorous mammalia are richer in calcium salts than 
the bones of carnivora and reptiles. 

The bones of the limbs contain more inorganic 
mineral matter than those of the trunk ; the humerus 
and femur contain more than the other long bones ; 
these also contain less fatty matters than the short 
bones : the flat bones contain the largest proportion of 
water. 

According to Fremy, the bones are not formed by an 
incrustation of the mineral portion in the cartilaginous 
tissue, as is generally believed, but by a juxtaposition 
of osseous matter, particle by particle ; for the rudimen- 
tary parts of the bones of the foetus have the same 



GELATIN. 399 

composition as the bones of full-grown persons, and the 
composition of the bones does not essentially vary with 



C. Aeby (18-[2] 10-408) also is of the opinion 
that the cartilage and calcium phosphate of the 
bones are not combined, and that the organic foun- 
dation of the bones simply induces ossification with- 
out entering into chemical relations with the calcium 
phosphate. 

Bones are used in the arts for the manufacture of 
animal charcoal or bone black, phosphorus, and 
gelatin. Grease is likewise extracted from them. 
They also serve as material for a great variety of useful 
and fancy articles. 

Gelatin. — The organic portion of bones is separated 
from the mineral portions on treatment with dilute 
hydrogen chloride. The salts are thereby dissolved; 
this organic substance alone remains, and, while retain- 
ing the form of the bone, is flexible, yellowish, and 
translucent. This substance, formed almost exclusively 
of ossein, becomes hard on drying, and again pliable 
and elastic Avhen placed in water for a short time. 
Submitted to the action of boiling water, it is trans- 
formed into gelatin. In making gelatin bones are first 
treated with boiling water. The grease is thereby 
separated out and removed. The bones are then placed 
in a digester with water, and submitted to a pressure 
of several atmospheres ; the gelatin is almost completely 
dissolved, and the mineral portion remains insoluble. 
These degelatinized bones form an excellent manure. 



400 ANIMAL CHEMISTRY. 

The transformation of ossein is more rapid with, the 
bones of a young animal than those of an adult. 

The ossein is not combined with the calcium, as 
can be very easily proven, for, if a few grammes of bones 
and a quantity of ossein equal in weight to that which 
exists in these bones be treated with boiling water the 
transformation is as rapid in one case as in the other, 
during the first part of the process. 

The proportion of gelatin produced by the bone then 
diminishes ; but this is due to the fact that the calcium 
salts of the exterior layers protect the interior portions 
from the action of the boiling water ; but if the surface 
of the bone be scraped the action of the boiling water 
again commences. 

Pure gelatin, C 6 H 10 N 2 O 2 (?), when dry is colourless, 
or very slightly yellow ; elastic and insoluble in alcohol 
and ether. It swells in cold water, and dissolves in 
boiling water. It turns the plane of polarization to the 
left. The solution, on cooling, changes into a gela- 
tinous mass, provided it has not been boiled too long 
with water. One per cent, of gelatin is sufficient to 
form a jelly; and sulphuric acid* converts it into gly- 
cocol. It forms with tannin an insoluble and impu- 
trescible compound, and this chemical action is the 
basis of the art of tanning. C. Yoit (11-8-297) 
has shown that gelatin is capable of partially replacing 
albumen and fat, as a food. 

Pathological States. — In arthritis, or gout, the arti- 
culations become encrusted with concretions, called 
arthritic calculi. 



EXOSTOSIS CARIES. 



401 



ARTHRITIC CONCRETIONS. 



Water 


. 10.3 


Animal matter . 


. 19.5 


Uric acid . 


. 20.0 


Sodium hydrate . 


. 20.0 


Lime .... 


. 10.0 


Potassium chloride 


. 2.2 


Sodium chloride 


. 18.0 




100.0 




(Sebastian). 



Exostosis is an affection in which osseous tumours are 
developed on the bone. An analysis gave : — 





Exostosis. 


The bone in 
the vicinity. 


Organic substance . 


. 46.0 


41.6 


Calcium phosphate 


. 30.0 


41.6 


„ carbonate 


. 14.0 


8.2 


Soluble salts . 


. 10.0 


8.6 



100.0 



100.0 



In caries of bone the inorganic portion of the bone 
is destroyed, while the organic portion remains almost 
intact. We owe to Yon Bibra the following analyses 
of cases of caries : — 



402 ANIMAL CHEMISTRY, 



Tibia at the 

point 
amputated. 


Tibia taken 

6 centimetres 

from the 

joint. 


Portion of the 

Astragalus 

taken from the 

centre of 

the caries. 


Inorganic substances 61.80 


42.10 


18.54 


Organic „ 38.20 


57.90 


81.46 



100.00 100.00 100.00 

In rachitis the mineral portion is removed to such an 
extent that the bones become incapable of supporting 
the body. The ossein is also changed, since boiling 
water no longer furnishes gelatin with these bones. 

Bones of a rachitic child, analyzed by Marchand, 
contained : — 





Vertebra. 


Femur. 


Radius. 


Sternum. 


Cartilages 


75.22 


72.20 


71.25 


61.20 


Fat 


6.12 


7.20 


7.50 


9.34 


Calcium phos- 










phates 


12.56 


14.78 


15.11 


21.35 


Magnesium 










phosphates . 


0.92 


0.80 


0.78 


0.72 


Calcium car- 










bonate 


3.20 


3.00 


3.15 


3.70 


Calcium sul- * 


) 








phate . 
Sodium sul- 


I 0.98 


1.02 


1.00 


1.68 


phate , 


) 








Sodium chlo- 










ride, calcium 










fluoride, 










iron, etc. 


1.00 


1.00 


1.20 


2.01 



100.00 100.00 100.00 100.00 



DENTAL TISSUES. 403 

Osseous tissues gradually decompose after death. In 
time nothing remains but the mineral portions, yet 
this action is very slow, as organic matter has been 
found in bones buried for several centuries. The 
character of the soil or other medium in which bones 
are placed has a great influence upon the rapidity of 
this change. 

The ossein which has not yet been wholly decom- 
posed has the same characters as ossein from fresh 
bones; it is capable of furnishing gelatin. 

Dental Tissues. — Three subsb.noes are distin- 
guished in the teeth : the dentine, ' which forms the 
greater part of the teeth ; the cement, which covers the 
cervix and roots ; and the enamel 

The cement has a structure, similar to that of the 
bones. It has a cavity which contains the nerves and 
blood-vessels, and in which arise the little canals which 
ramify and penetrate to the surface of the teeth. 
Treated with an acid, it parts with its inorganic con- 
stituents, and there remains an organic residue capable 
of furnishing gelatin, according to some authors, though 
denied by Hoppe-Seyler. The cement has the com- 
position, substantially, of the bones. 

The enamel is hard and brittle ; it contains about 
90 per cent, of calcium phosphate, and a considerable 
quanity of calcium fluoride, and only 2 to 6 per cent, 
of organic substances. When treated with dilute 
hydrogen chloride, the calcium phosphate dissolves, 
and prismatic fibres remain, which are not attacked by 
boiling water, and comport themselves like epithelium, 



:04 



ANIMAL CHEMISTRY. 



Berzelius found in the teeth : — 
Organic matter . 
Calcium phosphate 
Magnesium phosphate. 
Calcium carbonate 
Sodium „ and chloride 

Water, animal matter, alkali (traces) 



28.0 
64.4 
1.0 
53 
1.3 
0.0 

100.0 



The inorganic portion, according to Fremy, con- 
sists of: — 

Ash Calcium Magnesium Calcium 

Phosphate. Phosphate. Carbonate. 

Dentine . 76.8 70.3 4.3 2.2 

Cement . 67.1 60.7 1.2 2.9 

Enamel . 96.9 90.5 traces 2.2 



Minute amounts of chlorine and fluorine exist especially 
in the enamel. 

The following are more recent analyses by Aeby : — 





Cement. 


Dentine. 


Calcium phosphate . 


91.32 


93.35 


„ oxide 


. 5.27 


0.86 


„ carbonate . 


. 1.61 


4.80 


„ sulphate . 


. 0.09 


0.12 


Magnesium carbonate 


0.75 


0.78 


Ferric oxide . 


. 0.10 


0.09 


Organic substances . 


27.70 


3.60 



CHEMISTRY OF THE EYE. 



405 



Molar teeth, appear to contain more mineral matter 
than incisors (Bibra). The relation of the calcium 
phosphate to the calcium combined with carbonic acid, 
and in some analyses with chlorine and fluorine, 
suggests an analogy between the composition of the 
enamel and the mineral apatite. 



CHEMISTRY OF THE EYE. 



The sclerotic coat dissolves almost completely in 
boiling water, and the liquid obtained is a solution of 
gelatin and chondrin. 

The cornea furnishes chondrin with boiling water ; 
it also contains myosin and an alkaline albuminate. 

The choroid coat, on being boiled with water, also 
furnishes gelatin. 

The following analysis of the crystalline humour was 
made by Berzelius : — 



Water .... 


. 58.0 


Albuminous matter 


. 35.9 


Aqueous extract and salts . 


. 2.4 


Alcoholic extract 


. 1.3 


Membrane . 


. 2.4 



100.0 

The albuminous matter coagulates in certain cases, 
and cataract is then produced, on account of the opacity 
of the crystalline lens. 



406 ANIMAL CHEMISTRY. 

Lassaigne analyzed the opaque crystalline lens of the 
eye of a horse, and found — 

Coagulated albuminous matter . . 29.3 

Calcium phosphate . . . .51.4 

„ carbonate . . . .1.6 

Portion soluble in water . . .17.7 



100.0 



The iris is composed chiefly of fibrin. * 
The retina is an expansion of the optic nerve, which 
has the composition — 

Water 92.90 

Albumen 6.25 

Fatty substances 85 



100.00 



Aqueous Humour of the Eye. — Berzelius found 
in this liquid — 

Water 98.10 

Lactate, chloride of sodium . • 1.15 
Sodium hydrate 0.75 



100.00 
It also contains a small quantity of albumen. 



pus. 407 



EXUDATIONS. 

The name exudations is given to liquids formed at 
the expense of the blood, in consequence of an inflam- 
mation which arrests the circulation of this fluid. 

Exudations differ from transudations by containing 
fibrin, much albumen and blood globules, and in 
being more dense. 



pus 

Is a yellowish-white, viscous, neutral liquid, or 
alkaline if the pus is unhealthy. 

It is formed, like the blood, of a liquid {serum) in 
which are corpuscles. These are about .01 mm. in 
diameter ; they contain a viscous liquid and nuclei 
enclosed in a membrane. The colourless globules of 
mucus and lymph resemble these corpuscles ; they are 
designated in general as cystoid corpuscles. 

Pus exposed to the air usually becomes acid, pro- 
ducing margaric, butyric, and other homologous acids. 
Ammonium sulphide is afterwards formed, and the mass 
undergoes putrid fermentation. 



408 



ANIMAL CHEMISTRY. 



Pus contains 15 to 16 per cent, of soluble matter, the 
most important of which is albumen. The existence of 
a substance called pyin has been detected in it. but 
according to Lehman this body is an abnormal product. 
It generally contains a larger proportion of soluble salts 
than the serum of the blood. 

Boedecker found in a pus slightly alkaline : — 



Water . 


. 88.76 


Albumen ..... 


. 4.38 


Pyin. ..... 


4.65 


Fatty bodies and cholesterin 


1.09 


Sodium chloride 


0.59 


Other alkaline salts . 


0.32 


Earthy phosphates . 


0.21 



100.00 



Certain varieties of pus have the property of impart- 
ing a blue tinge to linen. Fordos has discovered the 
principle which produces this coloration : it is a 
eiystalline substance which he has named pyocyanin. 

Pus swells, and assumes the appearance of gelatin on 
being mixed with ammonium hydrate. This reaction 
distinguishes it from mucus. 

Pure pus, placed in a vessel and allowed to remain 
for several hours, separates into two layers. The lower, 
curdy layer contains the globules and the solids; the 
upper, opalescent layer constitutes the serum. 



PU& 



409 



C. Eobin gives the following analysis of the serum in 

1,000 parts: — 



Water .'._.. 


937.86 to 970.55 


Sodium phosphate . 


3.11 


J5 


4.66 


Phosphate of soda . 


traces 


» 


2.22 


Earthy and ammonio- 








magnesium phosphates . 


0.50 


J> 


2.20 


Sulphates and carbonates 








of sodium and potassium 


1.87 


5> 


3.11 


Salts of iron and silica 


.16 


5J 


.96 


Salts with organic acids 








formiates, butyrates. 








valeriates, etc. 


traces 


» 


1.00 


Leucin, tyrosin, and ex- 








tractive substances 


15.00 


J> 


20.00 


Serolin . 


1.00 


)> 


8.30 


Cholesterin 


3.50 


J> 


10.00 


Fatty bodies . 


10.00 


)> 


19.00 


Lecithin . 


6.00 


>J 


10.00 


Meta-albnmen and serin . 


11.00 


J? 


48.00 


Among the extractive subst 


ances there 


have been 


found : Paraglobulin, tyrosin, 


leucin, 


xanthin, urea, 


glucose (in diabetes), bilirubi 


n, uric * 


md 


chlorrho- 


dinic acids (in necrosis), and 


a special 


pus product, 


hydropsin. 









410 



LIST OF OKIGINAL AUTHORITIES. 



1. Annalen der Chemie und 

Pharniacie ; y. Liebig u. 
Wohler. 

2. Annalen der Physik und 

Chemie von Poggendorf . 

3. Archiv der Pharmacie. 

4. Bulletin de la societe d'en- 

conrag. 

5. Bulletin de la societe de 

Mulhouse. 

6. The Engineer. 

7. Chemisches Centralblatt. 

8. Chemical News. 

9. Comptes rendus. 

10. Deutsche Industriezeit. 

11. Zeitschrift fiir Biologic 

12. Gewerbeblatt, Sachsisches 

13. ,, Breslauer. 

14. „ Hessisches. 

15. „ "Wurtemberger. 

16. Wieck's Illustr. deutsch. 

Gewerbztg. 

17. Journal de Pharmacie et de 

Chimie. 



18. Journal fiir praktische 
Chemie. 

Bayr. Industrie u. Grewerbe- 
blatt. 

London Journal of Arts. 

Lehrbuch der physiolog. 
Chemie. Gorup-Besanez. 
Fourth Ed. 1878. 

Mittheilungen des Gewer- 
bevereins fiir Hannover. 

Reimann's Farberzeitung. 

Pharmaceut. Centralhalle v. 
Hager. 
25. Photogrr. Archiv. v. Liese- 



19. 

20. 
21. 



22. 

23. 
24. 



26. Polytechn. Centralblatt. 

27. Mechanics' Magazine. 

28. Dingier' s Polytechn. Journal. 

29. Polytechn. Eotizblatt v. 

Bottger. 

30. Milchzeitung (Dantzic). 

31. Practical Mechanics' Journal. 

32 . Quarterly Journ . of the Chem. 

Soc. 



LIST OF ORIGINAL AUTHORITIES. 



411 



33. Ackermann'sGewerbezeitung 

34. Repertory of patent inven- 

tions. 

35. Technologiste. 

36. Jahresbericht der Chemie 

37. Zeitschrift fur analytische 

Chemie. 

38. Journal of Applied Chemistry. 

39. Zeitschrift des allgem. oster- 

reich. Apotheker-Yereins. 

40. Pharmaceut. Zeitschr. f. 

Russland. 

41. Wien. Acad. Ber. 

42. Neues Jahrbuch fur Phar- 

macie. 

43. Berg- and huttenmann. 

Zeitung. 

44. The Lancet (London). 

45. Der Bierbrauer (Leipsic), 

46. Archiv. Pharm. 

47. Gazetta Chimica Italiana 

48. Eisner's Chem. -techn. Mitt- 

heilgn. 

49. Industrieblatterv. Hager und 

Jacobsen. 

50. Photographische Mittheilun- 

gen v. H. Yogel. 

51. Zeitschrift des Yereinsfur die 

Riibenzuckerindustrie 

52. American Jour, of Pharmacy. 

53. Photographische Correspon- 

ded v. Hornig. 

54. Bulletin beige de la photo- 

graphie par Deltenre- 
Walker. 

55. London . Royal Society Pro- 

ceedings. 



56. Chemisch-Technisch Reperi- 

torium. • 

57. Neue Deut. Gewb.-Zeitg. 

58. Wagner's Jahresbericht der 

chem. Technologie. 

59. "Wurzburg. gemeinn. Woch- 

ensclir. 

60. Berichte der deutschen chem. 

Gesellschaft. 

61. Proceedings of the French 

Association for the Ad- 
vancement of Science. 

Lyon Medicale. 

Scientific American. 

American Artizan. 

Journal fur Gasbeleuchtung. 

Moniteur Scientifique 

Badische Gewerbezeitung. 

Der Naturforseher (Berlin). 

Deutsche Weinzeitung. 

Annales du Genie civil. 

Les Mondes. 

Annales de Chimie et de 
Physique. 

Deutsche Gerberzeitung. 

Chicago Pharmacist. 

Neues Repert. der Pharm. 

Nature (London). 

Racquet's Modern Chemistry. 

Schweizer. Zeitschr. f . Phar- 



62. 
63. 
64. 
65. 

66. 
67. 
68. 
69. 
70. 
71. 
72. 

73. 
74. 
75. 
76. 

77. 
78. 

79, 

80. 
81. 

82. 



macie. 
Yir chow's Archiv. 
American Journal of Science. 
Zeitschrift f. d. gesammten 

Eaturwissenschaften. 
Zeitschrift fur Chemie. 



83. Photographic News. 



412 



LIST OF ORIGINAL AUTHORITIES. 



84. Brit. Journ. of Photography. 

85. New Remedies. 

86. Philadelphia Photographer. 

87. London Medical News. 

88. Monitenr Industriel. 

89. Jahresbericht der Thier- 

chemie. 

90. Centralblatt f. d. Papier- 

fabrik. 

91. Engineering. 

92. Propagation Indnstrielle. 

93. Journal de 1' Agriculture p. 

Barral (Paris). 

94. Proceedings of the Am. 

Pharm. Ass'n. 

95. Revista Pharmaceutica 

(Buenos Ayres). 

96. Journal for Pharmaci 

(Copenhagen). 

97. Bulletin de la Societe Chi- 

mique (Paris). 

98. Popular Science Monthly. 



99. Journ. of the Franklin In- 
stitute. 

100. American Chemist. 

101. Kun st und Glewerbe (Nurem- 

berg). 

102. NeuesHandwoerterbuchder 

Chomie. 

103. Jacobsen's Chem.-tech. 

Repertorium. 

104. Philosophical Magazine 

(London). 

105. Pharm. Journal and Trans- 

actions. 

106. Pharm. Zeitung (Bunzlau). 

107. Zeitschrif t f ur Chem. Gross- 

gewerbe. 

108. Die Chem. Industrie auf der 

Austellung in Philadel- 
phia. 

109. Zeitschrift fur Physiolog. 

Chemie. Hoppe-Seyler. 

110. Moniteur de la teinture. 



INDEX. 



PAGE. 

Acenapthene, Ci2Hio=i54. . 38 
Acetamide, C2 H 5 NO=S9- . J 3 6 
Acetanilide, Cs H a NO=i35. 130 
Acetic oxide C4 H6 O3 =102 103 

Acetochlorhjdric glycol 63 

Acetone, C 3 H6 0=58 99, 108 

Acetyl acetate, C4 N9 O3 ... 103 
Acetyl chloride, C 2 C1H 3 O. 103 
Acetyl hydride or aldehyd, 

C 2 H 4 0=44 86 

Acetylamine, C2 H5 N=43.. 129 
Acetylene, C2 H2 =26. . . . . 18 

Acetylide, cuprous 19 

Acid,acetic, C2 H4 Og =60. . 99 
Acid, aconitic, Cq Hq Oq =95 174 
Acid, acrylic, C3 H4 O2 =72. 91 
Acid, adipic, C6 H10O4 =148 91 
Acid, alloxanic, C4 H4 N 2 O5 125 
Acid, alpha-cymic, C11H14O2 91 
Acid, amalic, C6 H7 N2 O4 . . 169 
Acid, anchoic, C9 H16O4 =188 93 
Acid, angelic, C5 Hs O2 =108 91 
Acid, anisic, Cs Hs O3 =152. 92 
Acid, arabic, C6 HioOg —342 217 
Acid, arichidic, C20H40O2 . . 90 
Acid, atropic.Cg Hs O2 =148 164 
Acid, benzoic, C7 H6 O2 =126 

91, 109, 126 

Acid, benzoglycolic 126 

Acid, butyric,C4 Hs O2 . ..90, 108 
Acid, caffetannic 196 



PAGE. 

Acid, camphic, CioHi6020=9i 168 
Acid, campholic, C19H18O4 . . 91 
Acid, camphoric,CioHi804 41, 93 
Acid, caprylic, Cs H16O2 ... 90 
Acid, caproic,C6 H12O2 =116 90 
Acid, capric, C10H20O2 =172 90 
Acid, carballylic, C6 Hs 06 . 95 
Acid, carbamic, CH3 NO2 ... i-l 
Acid, carbazotic,(Picric) 

CH 3 N 3 07=229 33 

Acid, carbolic,C6 H6 = 94. 32 
Acid, carbonic, C2 H 3 = 62. 92 

Acid, catechic 196 

Acid, cerotic, C2TH54O. ..90, 180 
Acid, chelidonic, C7 H4 C>6 .. 95 
Acid, chlorbenzoic,C7 H5 CIO 

= i3 -5 l6 ° 

Acid, cholalic, C24H40O5 =408 95 
Acid, cholesteric, Cs H10O5 .. 95 
Acid,choloidic,C24H3s04 = 390 94 
Acid, cinnamic, C9 Hs O2 = 

148 91, in 

Acid, citraconic, C5 He O4 93, 121 
Acid, citric, C 6 H 8 07,H 2 = 

192+18 120, 95 

Acid, coccinic, Q3H26O2 ... 90 
Acid, comenic, C6 H4 O5 .. . 95 
Acid, coumaric, C9 Hs O3 . . 93 
Acid, croconic, C5 H 2 O5 . . 95 
Acid, crotonic,C4 H6 2 ..91, 178 
Acid, cumic, C10H12O2 = 164 91 



414 



INDEX. 



PAGE. 

Acid, cyanacetic, 

C 2 H 3 (CN)0 3 =85 103 

Acid, cyanhydric,HCN = 2 7. 161 

Acid, dextroracemic 117 

Acid, dialuric, C4 H4 N2 O4 125 
Acid, dinitrobenzoic, 

CtH 4 (N0 2 )2 2 =2I2... 1 10 
Acid, doeglic, C19H36O2 =296 91 

Acid, elaidic 177 

Acid, erucic, C22H42O2 =338. 91 
Acid, ethalic, C16H32O2 =256 179 
Acid, ethylsulphuric, 

C 2 H 5 HSO4 =126 71 

Acid, formic, CH2 O2 =50.98, 90 
Acid, fumaric,C4 H4 O4 =116 93 
Acid, gallic, C7 H 6 O5 . .95, 197 
Acid, glucic, Q2 Hg O9 =306 186 
Acid, glyceric, C 3 H 6 O4 . . . 93 
Acid, glycolic, C2 H4 O3 .60, 92 
Acid, guaiacic, C6 Hg O3 . . . 92 
Acid, gummic, C12 H22 On.. 217 
Acid, hippuric, C9 H9 NO3 .. 125 
Acid, insolinic, C9 Hg O4 . . . 94 
Acid, itaconic, C5 H6 O4 . . 121 
Acid, lactic, C3 H6 O3 ..92, 122 
Acid, lauric, C12H24O2 =200 90 
Acid, leucic, C6 H12O3 = 132. 92 
Acid, lichenstearic, C9 H14O3 92 
Acid, lithic, C5 H4 N4 O3 . . 123 
Acid, lithofellic, C20H36O4 . . 93 
Acid, malic, C4 H6 O5 =134 115 
Acid, malonic, C3 H4 O4 . . . 93 

Acid, mannitic 183 

Acid, margaric, C17H34O2 ... 177 
Acid, meconic, C~ H4 O . . . . 143 
Acid, melissic, C30H60O2 . . 90 



PAGE. 

Acid, mellitic, C4 H2 O4 94 

Acid, mesoxalic, C3 H2 O5 . . 94 

Acid, metagummic 217 

Acid, monochloracetic, 

C2 CI H 3 O2 =94.5 201 

Acid, moringic, C15H28O2 . . 91 

Acid, morintannic 196 

Acid, mucic, C6 H 3 Og =205 95 
Acid, myristic, Ci4H2gC>20. . ■ 90 
Acid, cenanthalic, C7 H14O2 90 
Acid, cenanthic, Ci4H2g03 . . 92 
Acid, oleic, CigH^C^ =282. 91 

Acid, opianic 127 

Acid, oxalic, C2 H2 O4 . ..93, 112 
Acid, oxamic, C2 H3 NO3 . . 11 
Acid, oxybenzoic, C7 H6 O3 195 
Acid, oxybutyric, C4 Hg O3 92 
Acid, oxycuminic, CioH^Os 92 
Acid,oxynapthalic, C10H6 O4 94 
Acid, oxy valeric, C5 H10O3 . . 92 
Acid, palmitic, C16H32O2 .90, 177 
Acid, parabanic,C3 H2 N2 O3 125 
Acid, parafinic, C24H4g02 . . 23 

Acid, paralactic 122 

Acid,paramalic, C4 H4 O4 . . 116 

Acid, paratartaric 117 

Acid, pectic, C16H22O5 =294. 218 

Acid, pectosic 218 

Acid, pelargonic, C9 HigC>2 ... 90 
Acid, phenic, Cg H 6 0=94. . 32 
Acid, phenylsulphuric, 

C 6 H 6 oIs=i7 4 32 

Acid, phloretic, C9 H10O3 . . 92 
Acid, phtalic,Cg H 6 O4 =150 94 
Acid, physetoric, C16H30O2 .. 91 
Acid, picric, C 6 H 3 (NO2 )a O 33 



INDEX. 



415 



PAGE. 

Acid, pimelic, C7 H12O4 .... 93 
Acid, pinaric,C2oH3o02 =3° 2 4 1 
Acid, pinic, C20H30O2 = 302 . . 91 
Acid, piperic, C12H10O4 =218 94 
Acid, propionic, C3 H6 O2 78, 90 

Acid, prussic, HCN=27 161 

Acid, pyrogallic, C6 H6 O3 . . 198 

Acid, pyroligneous 100 

Acid, pyromeconic, C5 H4 O3 92 
Acid, pyrotartaric, C5 H 8 O4 

= i3 2 93, n7 

Acid, pyroterebic, C6 H10O2 . . 91 
Acid, pyruvic, C3 H 4 O3 =88 92 
Acid, quinic, C7 H12O6 =144- 93 

Acid, quinotannic 196 

Acid,racemic,C4 H 6 06 =150 117 
Acid, ricinoleic, C18H34O3, 92, 180 
Acid, roccellic, C17H32O4 . . 93 
Acid, salicylic, C7 H 5 O3 195,32,92 

Acid, sarcolactic 122 

Acid, scammonic, C15H28O3 92 
Acid, sebic, C10H18O4 =202.. 93 
Acid, sorbic, C6 Hg O2 =112. 91 
Acid, stearic, C18H36O2 . .90, 177 
Acid, suberic,C8 H14O4 =174 93 
Acid, succinic, C4 H 6 O4 93, 115 
Acid, sulphocarbolic, 

C 6 H 6 S04=i74 33 

Acid, sulphoglucic 185 

Acid, sylvic, C20H30O2 =302. 41 
Acid, tannic, C2tH220i7=6i8 J96 
Acid, tartaric,C4 H6 06 . ..116, 95 
Acid, tartrelic, C4 H4 O5 . . . 117 
Acid, tartronic, C3 H4 O5 . . 94 
Acid, terebic,C7 H10O4 =158 93 
Acid, terechrysic, C6 He O4 94 



PAGE. 

Acid, thionuric,. 

C 4 H 5 N0 3 S03=i9S.... 125 
Acid,* thymotic, C11H14O3 .. 92 
Acid, toluic, Cs Hg O2 =136 91 
Acid, trichloracetic, 

HC 2 Cl 3 2 = 163.5 102 

Acid, tropic, C9 H10O3 =166. 164 
Acid, uric,C5 H4 N4 O3 = 168 123 
Acid, valeric or valerianic, 

C6 H10O2 = 102 109, 90 

Acid, veratric, C9 HiqOs ... 94 
Acid, xylic, C9 H10O2 =150. 91 

Acids 95 

Acids, aromatic 91 

Acids, fatty 90 

Acids, general methods of 

preparation, 96 

Acids, organic 90 

Acids, defined 95 

Acids, polyatomic 112 

Acids, pyro 97 

Aconitina, C30H47NO7 =533. 165 

Albumen 228 

Alcohol, amy lie, C5 H12O . 56, 45 
Alcohol, benzyl, C7 H 8 0=io8 

46 

Alcohol, butyl, C4 HioO = 64 45 
Alcohol, eery 1,C27H560 = 396 45 

Alcohol, cholesteryl 46 

Alcohol, cinnyl, C9 H10O . . 46 

Alcohol, cuneol 46 

Alcohol, cymol, C10H14O . . 46 
Alcohol, melissic, C30H62O. . 180 
Alcohol, methyl, CH4 O. .45, 46 
Alcohol, myricyl, C30H62O.. 45 
Alcohol, octyl, Cs Hi 8 0=i30 45 



416 



INDEX. 



PAGE. 

Alcohol, ordinary, or ethyl, 

C 2 H 6 0= 4 6 49 

Alcohol, propyl, C3 H 8 O.... 45 
Alcohol, sexdecyl, C16H34O.. 45 

Alcohol, sextyl, C6 H14O 45 

Alcohol, vinyl, C2 H 6 0=46 45 
Alcohol, xylyl,C8 HioO= 122 46 

Alcohols, diatomic 58 

Alcohols, monatomic 44 

Alcohols, polyatomic. , 59 

Alcohols, sulphur 82 

Alcohols, selenium 82 

Alcohols, tellurium 82 

Alcohols, tetratomic 59 

Alcohols, triatomic 64 

Aldehyds 86 

Alizarin, C10H6 O3 =174. . . 39 

Alkalamides 136 

Alkaloids 127 

Allantoin, C4 H 6 N 4 O3 = 158 

124 

Alloxan, C4 H4 N 2 O5 =160. 125 
Alloxantin, Cs H10N4 O10. . 123 
Allyl iodide, C 3 H 5 I=i68. . 57 
Allyl sulphide, C$ HioS= 114 57 
Allyl sulpho-cyanide, 

C4H 5 NS = 99 57 

Allylamine, C3 H7 N=57. . . 127 

Allylene, C3 H4 =40 20 

Amane, C5 Hi 2 =72 23 

Amber 26, 42 

Amides 136 

Amidoxypropyl, 

C 3 H4(NH 2 )0=72 75 

Amines 133 

Ammelide 172 



PAGE. 

Ammonia aldehydate, 

C 2 H 4 ONH 3 =6i 87 

Ammonia citrate of iron. . . 121 

Ammoniacum 43 

Ammonias, compounds 131 

Ammonium, cyanate,CH4 N 2 172 

Ammoniums 137 

Ammoniums, quarternary. . 136 

Amvgdalin, QoH^NOn 193 

Amyl, acetate, C7 H14O3 . . 56 

Amyl, chloride, C5 HnCl . . 56 

Amyl, hydride, C5 Hi 2 =72. 23 

Amylamine, C5 Hi3N = 87. . 121 

Amylene, C5 Hio= 70 23 

Anhydride, tartaric, 

C4 H4O5 =132 117 

Aniline 30, 127, 131 

Anthracene, Ci4Hio=i78. .29, 39 

Arabin Ci 2 H 22 On=342 217 

Arbutin C13H16O7 =284 193 

Aricina C23H26N2 O4 =397- . 129 

Arnicin 42 

Aromatic compounds 89 

Arsines 128 

Asphalt 26 

Assafcetida 43 

AtropiaCnH23N03 =289.164,129 

Balsams 41 

Bases organic, 125 

Bases quarternary, 136 

Bassorin 218 

Belladona 164 

Benzene C6H6 =78 27 

Benzine 24 

Benzoic aldehyd, C7 H 6 O.. 86 

Benzol, C 6 H 6 =78 27 



INDEX 



417 



PAGE. 

Benzone 119 

Benzonilrile no 

Benzyl chloride 126 

Benzylene 20 

Bezoar 267 

Bidecane 28 

Bidecyl hydride 23 

Bilifulvin 257 

Bilirubin 257 

Biliverdin 257 

Bile 250 

Bile, action on food 258 

Bitumen 26 

Biuret 172 

Blood 272 

Blood, action of different 

gases on the 291 

Blood, chemical pathology 

of the 294 

Blood, coagulation of 276 

Blood, gases of the 288 

Blood globules 281 

Blood, iron of the 287 

Blood, uses of 293 

Bones 399 

Borneol 58 

Brain constituents 394 

Brandy 52 

Brucia 161, 129 

Butane 23 

Butter 179 

Butyl hydride 23 

Butylamine 128 

Butylene 20, 22 

Cacodyl 79, 105 

Caffeia (caffein) 130, 168 



PAGE. 

Campholic alcohol 117 

Camphor, artificial 37 

Camphor 40 

Camphor, monochlor 41 

Camphor, oxy- 41 

Camphor of Borneo 58 

Cantharidin 168 

Candles 1 76 

Cannabin 42 

Caoutchouc 36, 43 

Caprylamine 127 

Caramel 190 

Caramelane 190 

Caramelene 190 

Caramelin „ . . 190 

Carbo-hydrates, defined 7 

Carbon dioxide 313 

Caries 401 

Carbonic ether 74 

Cartilagein 392 

Casein, animal 226, 233 

Casein, vegetable 219, 234 

Castor oil 180 

Castorin 42 

Cellulose (cellulin) 202 

Cerasin 217 

Cerebrin , 395 

Cetene , 23 

Chitin 184 

Chloral 87 

Chloral hydrate 88 

Chloroform . . 47 

Chloropropyl ! 15 

Cholera 296 

Cholesterilene 255 

Cholesterin 255 



418 



INDEX 



PAGE. 

Cholesterophan 169 

Cholin 251 

Chondrin 227, 214, 392 

Chondroglucose 392 

Chyle 269 

Chyme 268 

Chymosine 247 

Cinchonia (cinchonine).i29, 156 
Cinchonicia (cinchonicine) . . 158 
Cinchonidia (cinchonidine) 

158, 129 

Cinnamene 38 

Coagulum 281 

Codeia 146, 129 

Colchinia 163 

Colloidin 375 

Collodion 208 

Colophony 41 

Compound ammonias 131 

Conia (conine) 141, 129 

Conicin 129 

Coniferin 193 

Convolvulin 193 

Conylia 141, 129 

Cotarnin 147 

Cream of Tartar 116 

Creatin 188, 386 

Creatinin 386 

Creosote 34 

Cresofol 29, 34 

Crotonylene 20 

Cumene 28 

Cumidin 127 

Cuprous acetylide 20 

Curari 163 

Curarina 162 



PAGE. 

Cyanopropyl 115 

Cyclamin 193 

Cymene 38 

Cymogene 24 

Cymol 41 

Cystin 353 

Daphnin 193 

Daturia, (atropia) 164, 129 

Decane 24 

Dextrin 212, 214 

Dental tissue 403 

Diabetes 327, 347 

Diastase 212 

Diethylamine 128 

Diethylpropyl 15 

Diethylenic diamine 170 

Digestion 237 

Digitalin 166 

Digitin 166 

Dimethylphosphine 128 

Draconyl 38 

Dropsy 297 

Dulcite, (dulcose) 183, 181 

Duodecylene 23 

Dysentery 266 

Dystisin 253 

Elaidin 175 

Elaine 175 

Elayl 21 

Elemi 43 

Emetia 167 

Emetics 119 

Emydin 226 

Ergotin 42 

Erythrite 49 

Esculin 193 



INDEX 



419 



PAGE. 

Essence of mirbane 29 

Essence of thyme 34 

Essential oil of cloves 37 

Essl. oil of bergamot 37 

Essl. oil of copaiba 37 

Essl. oil of cubebs 37 

Essl. oil of elemi 37 

Essl. oil of juniper 37 

Essl. oil of lemon 37 

Essl. oil of orange 37 

Essl.#oil of pepper 37 

Ethal 179 

Ethane 13, 15, 23 

Ethene 13, 15 

Ether, acetic 73 

Ether, butyric 81 

Ether, chlorhydric 75 

Ether, common 70 

Ether, cyanhydric 77 

Ether, ethyl 70 

Ether, formic 81 

Ether, hydriodic 76 

Ether, hydrosulphuric 83 

Ether, cenanthylic. ..'. 81 

Ether, oxalic 74 

Ether, oxamic 117 

Ether, sulphuric 70 

Ether, valerianic 81 

Ether, vinic 70 

Ethers 69 

Ethers, simple 69 

Ethers, compound 73 

Ethers, miscellaneous 81 

Ethers, mixed 38 

Ethine 13 

Ethyl 15 



PAGE. 

Ethyl chloride ^. 75 

Ethyl cyanide 77 

Ethyl formiate 9 

Ethylglycol 61 

Ethyl-hexyl ether 84 

Ethyl hydride 23 

Ethyl iodide 76 

Ethyl mercaptan 83 

Ethylmethylaniline 30 

Ethyl oxide ". . 69 

Ethyl sulphide 83 

Ethylamine , .... 132, 127 

Ethylene 21 

Ethylene bromide 61 

Ethylene chloride 76 

Ethylene oxide 62 

Eucalin 182 

Eye, chemistry of the 405 

Excrements 265 

Excretin 265 

Extosis 401 

Exudations 407 

Fats 174 

Fatty acid series 90 

Ferment, bile 258 

Fermentation, acetic 100 

Fermentation, alcoholic . . .49, 181 

Fermentation, gallic 197 

Fermentation, lactic 122 

Ferrocyanide of potassium . 172 

Fibrin 226, 23 1 

Flesh 382 

Flour 215 

Food, respiratory 223 

Food, plastic 224 

Food, transformation of. . . . 321 



420 



INDEX. 



PAGE. 

Formene 23 

Frankincense 43 

Fulminates 54 

Fusel or fousel oil 56 

Galactose 187, 182 

Gas, illuminating. 21 

Gasolene 24 

Gastric juice 242 

Gasterase pepsin 247 

Gelatin 234, 399 

Glucosane 185 

Glucose 180, 182, 184, 343 

Glucose in the liver 323 

Glucosides 192, 184 

Glue 235 

Gluten 216 

Glycerin 64 

Glycocol, zincic 126 

Glycogen 214, 250, 324 

Glycol, amyl. . . 59 

Glycol, butyl 59 

Glycol, diethyl 61 

Glycol, ethyl 61 

Glycol, hexyl 59 

Glycol, monochlorhydric. . . 62 

Glycol, octyl 59 

Glycol, ordinary 59 

Glycol, propyl 123 

Grape sugar 182 

Guano. 124 

.Gum 216 

Gum arabic 217 

Gum resins 41 

Gun-cotton 207 

Haematin 286 

Haematocrystallin 225 



PAGE. 

Haemoglobin 284, 226 

Helicin 194 

Heptyl hydride 23 

Heptane 23, 24 

Heptylene 22 

Hexadecane 24 

Hexadecyl hydride 24 

Hexane ,23 

Hexy lene 22 

Hexyl hydride 23 

Hoffmann's anodyne 73 

Homologous series 12 

Honey 192 

Hydrides 23 

Hydrocarbons 18 

Hydrocarbides 18 

Hydrocarbides, extra-terres- 
trial 40 

Hydrocephalus fluid 374 

Hydrogen carbides 18 

Hydropical fluid 375 

Hydrosulphuric Ether 83 

Hyosciamine 164 

Ictithin 226 

Indican 342 

Indigogen 343 

Indiglucin 343 

Indigo 130 

Inosite (inosin) 182 

Intestinal concretions 267 

Intestinal fluids 264 

Intestinal gases 265 

Inulin 214 

Iodomorphia 145 

Iron of the blood 287 

Isatin 38 



INDEX. 



421 



PAGE. 

Isologous series 12 

Isomerism 8 

Jalapin 193 

Jervia 163 

Kerosene 24 

Ketones 40 

Lactide 123 

Lactose orlactin.... 191, 182 

Leather 197 

Legamin 219 

Leucocythaemia 296 

Levulosan 190 

Levulose 187, 182 

Lichenin 214 

Lymph 270 

Madder 39 

Maltose 182 

Mannitane 183 

Mannite 181, 183 

Marsh-gas 23 

Meconin 143, 147 

Melampyrite 181 

Melanin 389 

Melezitose 182 

Melitose 182 

Mercaptans 82 

Metalbumen 225 

Metamerism 9 

Metaterebenthene 38 

Metastyrol 38 

Methane 13, 15, 23 

Methenyl 15 

Methyl 15 

Methyl acetate 9 

Methyl chloride 47 

Methyl cyanate 131 



PAGE. 

Methyl hydride 23 

Methylamine 131 

Methylethylamine 128 

Methylphosphine 128 

Methylpropyl 15 

Milk 376 

Molasses 189 

Monamines 133 

Monochlorcamphor 41 

Monochlorhydrin 66 

Morphia (Morphine) 143, 129 

Mucin 227 

Mucus 372 

Murexide 125 

Muscular power 316 

Muscular tissue 283 

Musculin 232 

Myosin 232 

Mycose 182 

Naphtha 24 

Naphthalamine 128 

Naphthalin 27, 38 

Narceia 148, 129 

Narcotina '. . 129 

Neocytes 337 

Neurin 257 

Nevrilemma 393 

Nicotina 139, 129 

Nicotyl 140 

Nicotylia 139, 129 

Nitrilebases 124 

Nitrobenzol 29 

Nitrogenous substances.... 223 

Nitroglycerine 66 

Nitryls, or cyanhydric ethers 134 

Nonane 23 



422 



INDEX. 



PAGE. 

Nonyl hydride 23 

Nonylene 22 

Nutrition 316 

Nutrition, role of mineral 

compounds in 330 

Octane 23 

Octylglycol 59 

Octyl hydride 23 

Octylene 22 

Oils, fatty 174 

Oils, essential 36 

Olein 175 

" Oleomargarine" 179 

Oleo-resins 42 

Opium 142 

Orcin 193 

Organizable substances 205 

Organometallic compounds. 78 

Ossein. 226, 234 

Osseous tissues 399 

Oxamide 74 

Oxanthracene 39 

Oxycamphor 41 

Oxygen 311 

Pancreatic juice 261 

Pancreatin 262 

Para-arabin 192 

Paralbumen 226 

Plants, respiration of 201 

Plants, nutrition of 204 

Polyamines 170 

Polymerides 9 

Polymerism 9 

Populin 193 

Potassium, binoxalate 114 

Potassium, ferrocyanide . . . . 170 



PAGE. 

Paraffin , 22, 24 

Papaverin 129, 148 

Paramorphia 148 

Paramylene 22 

Parapeptone 249 

Pectin 218 

Pectose 218 

Pentadecane 24 

Pentadecyl hydride 24 

Pepsin 227, 247 

Peptones 225, 249 

Petroleum 24 

Phenol 32 

Phenol, potassic 32 

Phenol, trinitric 30 

Phenyl 30 

Phenyl hydrate 32 

Phenylamine 127 

Phlorizin 193 

Phlorylol 34 

Phosphines 128 

Phtalidamine 127 

Picrotoxin 160 

Pinite. 181 

Piperidine 141 

Piperine 141 

Pitch, Burgundy 42 

Plethora 295 

Potassium, formiate 88 

Propane 13, 15, 23 

Propenyi 15 

Propine 13. 

Propone 13 

Propyl 15 

Propyl hydride 23 

Propylamine 127 



INDEX. 



423 



PAGE. 

Propylene 22 

Proplene iodide 64 

Protein 225 

Ptyalin 212, 227, 238 

Pus 407 

Pyin 227, 407 

Pyocyanin 40S 

Pyrethrin 42 

Pyrocatechin 352 

Pyrolignite 106 

Pyroxylin 207 

Quercite 181 

Quercitrin 193 

Quinia, (quinine) 151, 129 

Quinicia 154, 129 

Quinidia 129 

Quinidia, oxalate of 155 

Quinoidin 158 

Quinolein, (quinolin) 130,153,157 

Quinovin 193 

Rachitis ..-.-. 402 

Radicles, defined 14 

Radicles, organometallic ... 78 

Radicles, organometalloid . . 81 

Reagent, Fehling's 187 

Reagent, Haines' 187 

Reagent, Trommer's 186 

Resins 25, 41 

Respiration 272, 301 

Retinasphalt 25 

Retinite 25 

Rhigolene 24 

Rice 216 

Rochelle salt 118 

Rosanilin 31 

Rutylene 20 



PAGE. 

Rye 216 

Saccharide 186 

Saccharoses 182 

Salicin 194 

Saligenin 194 

Saliva ; 237 

Saponification 176 

Saponin 193 

Scurvy 297 

Semen 371 

Serosity 374 

Serum 278 

Sinapolin 58 

Sinnamin 58 

Soaps 176 

Sodium ethyl 80 

Sodium sulphocarbolate. ... 33 

Solanidia (solanidine) 165 

Solania (Solanine),. . .165,129,193 

Sorbin 182 

Spermaceti. . 179 

Spirit of Mindererus 105 

Stannethyl 79 

Stannethyl iodide 79 

Starch 210 

Stearin (stearine) 174 

Stearine candles., 176 

Stercorin 257, 265 

Stibines ; 128 

Stibyl 119 

Strychnia (strychnine). .159, 129 

Styrol 38 

Sucrates 190 

Sugars 181 

Sugar of milk 191, 182 

Sweat . , 370 



424 



INDEX, 



PAGE. 

Synovia 374 

Syntonin 229, 232 

Tannin 196, 193 

Tartar emetic I .y.C/-**€-l 

Taurin ...7. 254 

Teeth 403 

Tetrachloropropyl 15 

Tetradecane 24 

Tetradecyl hydride 24 

Tetradecylene 22 

Tetrethylammonium 133 

Thebaia 148, 120 

Theia (theine) 168, 130 

Theobromin. 169, 130 

Thymol - 34 

Thiosinnamin 58 

Tissues 388 

Tissues, areolar 388 

Tissues, recticular 387 

Tissues, cartilagenous 391 

Tissues, nerve 393 

Tobacco 140 

Toluene 28 

Toluidin 127, 130 

Transpirations 370 

Trehalose 182 

Trichlorhydrin 66 

Trichloroxypropyl 15 

Tridecane 27 

Triedecyl hydride ,,,,,,.,,, 24 



PAGE. 

Tridecylene * 22 

Triethylamine 135 

Triethylarsine 128 

Triethylenic, diamine 170 

Triethylstibine 128 

Trimethlamine 128 

Trimethylphosphine 128 

Tunicin 184, 209 

Turpentine 35 

Tvpes, organic 10 

Typhoid fever 266, 296 

Urinary calculi 353, 368 

Urinary deposits 352, 364 

Urine 333 

Urine, analysis of 356 

Urochrome 343 

Uroglaucin 343 

Urorubrohsematin 352 

Urrhodin 343 

Uroxanthin 343 

Wax 179 

Whiskey 52 

Wines 32 

Wood spirit 49 

Xylene 28 

Xylidin 127 

Xylyl alcohol 46 

Zinc, ethyl 79 

Zinc, glycol 79, 126 

















■ 






. 



CONGRESS 




00055543172 







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§m 



